The standard deviation is the square root of the variance and is used to measure how spread out the data is. To calculate the standard deviation, take the square root of the variance.
What is variance?Variance is the measure of how far a set of numbers are spread out from their average value. It is a measure of how much variation or dispersion exists from the average. Variance is represented as the square of the standard deviation, which is a measure of the spread of numbers in a set.
The mean of the data is 18.25. The variance is a measure of the spread of the data away from the mean, and is calculated by taking the average of the squared differences from the mean. To calculate the variance, subtract the mean from each data point, square this result and add up the values. Then divide this sum by the number of data points minus one.
For example, if the data set contains the values 10, 15, 20, 25 and 30 then the mean is 18.25. Subtracting the mean from each data point gives -8.25, -3.25, 1.75, 6.75, 11.75. Squaring each of the differences gives 68.0625, 10.5625, 3.0625, 45.5625, 137.0625. Adding these results together gives 264.3125. Dividing this by 4 (the number of data points minus one) gives 66.075. Taking the square root of this gives 8.1 as the standard deviation.
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The variance of the given data is calculated to be 118.63 and the standard deviation is 10.89.
What does variance mean?The variance of the data is a measure of how far the data points are spread out from the mean. It is calculated by taking the differences between each data point and the mean, squaring the differences, and then taking the average of those squared differences.
For our data, the mean is 18.25. To find the variance, we can subtract 18.25 from each of the data points and square the differences. Then we can add up all of the squared differences and divide by the number of data points.
Variance = (2 - 18.25)² + (3 - 18.25)² + (4 - 18.25)² + (18 - 18.25)² + (20 - 18.25)² + (25 - 18.25)²
= (15.752 + 14.752 + 13.752 + 0.752 + 1.752 + 6.752) ÷ 6
= (255.2 + 217.2 + 190.2 + 0.6 + 3.0 + 45.8) ÷ 6
= 711.8 ÷ 6
Variance = 118.63
To find the standard deviation, we take the square root of the variance.
Standard deviation = √118.63
Standard deviation = 10.89
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Question:
The mean of the data is 18.25. Find the variance. Find the standard deviation.
Data: 2, 3, 4, 18, 20, 25
suppose you are in charge of a company that rents moving vans to customers. Each van costs $18,000, and you spend an average of $35 per rental day on maintenance costs. You rent the van for $59.99 per day. How could you set up a system of equations to find where your company "breaks even?" On average, how many days must one van be rented before the company makes any profit
The answer will be as follows after answering the supplied question After equation reaching the break-even threshold, the firm will begin to profit.
What is equation?A math equation is a process that relates two statements by using the equals sign (=) to indicate equivalence. In algebra, an equation is a mathematical statement that shows the equivalence of two mathematical expressions. In the equation 3x + 5 = 14, for example, the equal sign separates the numbers 3x + 5 and 14. A mathematical formula may be used to understand the link between the two phrases written on opposite sides of a letter. Frequently, the logo and the software are the same. For example, 2x - 4 = 2.
Rental rate per day x number of rental days Equals total revenue
Total revenue = $59.99 multiplied by
Total cost = vehicle cost + daily maintenance cost * number of rental days
Total expenditure = $18,000 + $35x
We can now put these two equations equal to determine the break-even point:
$59.99x = $18,000 + $35x
When we solve for x, we get:
$24.99x = $18,000
x = 720.29
We round up to 721 days since we can't rent a vehicle for a fractional amount of days.
As a result, in order to break even, the corporation needs rent a vehicle for at least 721 days.
After reaching the break-even threshold, the firm will begin to profit.
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Calculate the difference between the amount of commission for selling goods worth Rs.20 lakhs and Rs .30 lakes. Sales between 15-25 lakhs is 1% and sales between 25-54 is 1.5%.
The difference in commission for selling goods worth Rs. 20 lakhs and Rs. 30 lakhs is Rs. 7,500.
How to calculate the difference between the amount of commission for selling goods ?
The commission on sales worth Rs. 20 lakhs would be:
1% of (20 lakhs) = 0.01 x 20,00,000 = Rs. 20,000
The commission on sales worth Rs. 30 lakhs would be:
1% of (25 lakhs) + 1.5% of (5 lakhs) = (0.01 x 25,00,000) + (0.015 x 5,00,000) = Rs. 27,500
The difference in commission between the two sales would be:
Rs. 27,500 - Rs. 20,000 = Rs. 7,500
Therefore, the difference in commission for selling goods worth Rs. 20 lakhs and Rs. 30 lakhs is Rs. 7,500.
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Start by creating two different circles:
`◍ Create a point, and label it A. To make the remainder of the activity easier, choose integers for the x and y coordinates of point A.
◍ Create a circle with its center at point A and with a radius of your choice. To make the remainder of the activity easier, choose an integer value for the radius.
◍ Create another point, and label it B. To make the remainder of the activity easier, choose integers for the x and y coordinates of the point.
◍ Create a circle with its center at point B and with a radius of your choice that is different from the radius chosen for circle A. To make the remainder of the activity easier, choose an integer value for the radius
The integers and radius for different circles as instructed are; (1.) Circle A (1, 3) with r= 3 (2.) Circle B (5, 3) with r= 5.
How to create the circles with integers and radius as instructed?1. On a y and x graph, create a dot and get the integers for the dot which are the numbers you find when you trace the dot to the x and y axis.
Integers are a set of numbers that include positive numbers, negative numbers, and zero. Integers are whole numbers (not fractions or decimals) that can be represented on the number line. Examples of integers include -3, -2, -1, 0, 1, 2, 3, and so on.
For the diagram below, diagram A and B share a similar point at the y axis and a different point at the x axis. There integers are
A ( 1, 3) and
B (5, 3)
The radius of choice for A is r= 3
The radius of choice for B is r= 5
Therefore the diagram should look like the one in the attached file.
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If $4000 is invested at 7% interest per year compounded continuously, how long will it take to double the original investment?
it will take about 9.90 years to double the initial investment of $4000 at 7% continuous compound interest.
We can use the formula for continuous compound interest:
[tex]A = Pe^(rt)[/tex]
where A is the amount of money after time t, P is the principal (initial investment), r is the interest rate, and e is the mathematical constant approximately equal to 2.71828.
To find the time it takes to double the initial investment, we want to solve for t when A = 2P (twice the initial investment). Substituting the given values, we have:
[tex]2P = Pe^(rt)[/tex]
Dividing both sides by P, we get:
[tex]2 = e^(rt)[/tex]
Taking the natural logarithm (ln) of both sides, we have:
[tex]ln(2) = ln(e^(rt))[/tex]
ln(2) = rt * ln(e)
Since ln(e) = 1, we can simplify further to:
ln(2) = rt
Solving for t, we get:
t = ln(2) / r
Substituting the given values, we have:
t = ln(2) / 0.07
t ≈ 9.90 years
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Which of these vectors can be written as a linear combination of vector[-6,-4,7,1] and [-4,-3,2,-1]?
in vector D [-2,1,3,0], we can multiply [-6,-4,7,1] by -2 and [-4,-3,2,-1] by 1 and add the two results together to obtain [-2,1,3,0]. This means that vector D can be written as a linear combination of vector [-6,-4,7,1] and [-4,-3,2,-1], making it the correct answer.
We can use the concept of linear combinations to answer this question. A linear combination of two vectors is a vector that can be written as the sum of two or more vectors. To solve this problem, we need to express the four given vectors as a linear combination of vector [-6,-4,7,1] and [-4,-3,2,-1]. We can do this by multiplying each vector element by a scalar and then adding them together. For example, in vector D [-2,1,3,0], we can multiply [-6,-4,7,1] by -2 and [-4,-3,2,-1] by 1 and add the two results together to obtain [-2,1,3,0]. This means that vector D can be written as a linear combination of vector [-6,-4,7,1] and [-4,-3,2,-1], making it the correct answer.
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House Loan
Cost: $450,000
Length of Loan: 30 Years
Simple Interest Rate: 6.00%
Yearly Taxes: $2,000
Yearly Insurance: $1,500
What are your Monthly Payments with taxes & insurance:
Answer:
M = P [ i(1 + i)^n ] / [ (1 + i)^n - 1]
where M is the monthly payment, P is the principal (the cost of the house minus the down payment), i is the monthly interest rate (6.00% divided by 12), and n is the total number of payments (30 years times 12 months per year).
Plugging in the values, we get:
P = $450,000 - 0 (assuming no down payment)
i = 0.06 / 12 = 0.005
n = 30 x 12 = 360
M = $450,000 [ 0.005(1 + 0.005)^360 ] / [ (1 + 0.005)^360 - 1] = $2,695.55
So the monthly mortgage payment is $2,695.55.
To find the monthly payment with taxes and insurance, we need to add the yearly taxes and insurance and divide by 12 to get the monthly amounts. So:
Monthly Taxes = $2,000 / 12 = $166.67
Monthly Insurance = $1,500 / 12 = $125.00
Total Monthly Payment with Taxes and Insurance = $2,695.55 + $166.67 + $125.00 = $2,987.22
Therefore, the monthly payments with taxes and insurance for the $450,000 house loan are $2,987.22.
As given on the STEPS Engineers Ireland website ( Engineers Week, Secondary School section) how many free engineering activities are available to download by teachers for classroom use?
represent 1:50000 in 2 different method
The answer of the question based on the representing the value in two different methods are given below;
What is Distance?Distance refers to amount of space between the two objects or points in the space. It is measure of length of path traveled by object or person from one point to the another.
Distance can be measured in various units like meters, kilometers, feet, miles, etc. It is fundamental concept in a geometry and is used in a various areas of science, engineering, and everyday life.
1:50000 can be represented in two different ways as follows:
Ratio: The expression "1:50000" represents the ratio of one unit on a map to 50,000 units on the ground. This means that one unit of distance on the map corresponds to 50,000 units of distance on the ground. For example, if one unit on the map represents one meter, then 50,000 meters (or 50 kilometers) on the ground would be represented by one unit on the map.Decimal: 1:50000 can also be represented in decimal form as 0.00002. This is obtained by dividing 1 by 50,000, which gives the proportion of one unit on the map to the corresponding distance on the ground. This can be useful for calculations that involve scaling or converting distances between map and ground measurements.TO know more about Ratio visit:
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Traditionally, authors of textbooks on tests and measurements have suggested that, at a minimum, a test should have a test-retest reliability of .70 to be considered sufficiently reliable to use for the assessment of individuals. Using this criterion when evaluating the test-retest reliability coefficients for middle adolescents, which variables measured by the test are sufficiently reliable?
Based on the given criterion, the variables that are sufficiently reliable for middle adolescents are creativity, critical thinking, and cognitive ability
Traditionally, authors of textbooks on tests and measurements have suggested that, at a minimum, a test should have a test-retest reliability of .70 to be considered sufficiently reliable to use for the assessment of individuals. Using this criterion when evaluating the test-retest reliability coefficients for middle adolescents, the variables measured by the test that are sufficiently reliable are as follows:In this scenario, the variables measured by the test, which are sufficiently reliable for middle adolescents, can be determined by identifying the variables whose test-retest reliability coefficients are greater than or equal to 0.70. It can be observed that variables such as creativity, critical thinking, and cognitive ability are all variables that are considered reliable for middle adolescents. Therefore, based on the given criterion, the variables that are sufficiently reliable for middle adolescents are creativity, critical thinking, and cognitive ability.A reliability coefficient is a statistical method used to assess the reliability of a measurement by determining the consistency of scores obtained by the measurement instrument. A test-retest reliability is a statistical method used to determine the reliability of a test's measurements by comparing the scores obtained from taking the same test multiple times over a period of time. The coefficient of test-retest reliability measures the consistency of test scores over time, indicating whether a test is stable and reliable enough to be used as an assessment tool.
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A rectangle has a width of 3 cm and a length of 10 cm. what is the effect on the perimeter when the dimensions are multiplied by 10? responses the perimeter is increased by a factor of 10. the perimeter is increased by a factor of 10. the perimeter is increased by a factor of 40. the perimeter is increased by a factor of 40. the perimeter is increased by a factor of 100. the perimeter is increased by a factor of 100. the perimeter is increased by a factor of 400.
The perimeter of a rectangle is given by the formula P = 2(l+w), where l is the length and w is the width of the rectangle. The correct answer is that the perimeter is increased by a factor of 10.
In this case, the width is 3 cm and the length is 10 cm, so the initial perimeter is:
P = 2(10+3) = 26 cm
Now, if we multiply the dimensions by 10, the new length would be 10 x 10 = 100 cm and the new width would be 3 x 10 = 30 cm. The new perimeter would then be:
P' = 2(100+30) = 260 cm
Comparing the initial perimeter to the new perimeter, we can see that the new perimeter is 260/26 = 10 times larger than the initial perimeter. Therefore, the correct answer is that the perimeter is increased by a factor of 10
It's important to note that the word "factor" is often used to describe the degree to which something changes. In this case, a factor of 10 means that the new perimeter is 10 times larger than the initial perimeter. If we were to use the word "increase" instead, we would say that the perimeter is increased by 250% (or 2.5 times).
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A rectangular swimming pool is bordered by a concrete patio. The width of the patio is the same on every side. The area of the surface of the pool is equal to the area of the patio. What is the width of the patio?
Length times width = area of a rectangle.
16ft×24ft= 384
Area of the patio since all sides are equal to
4
width×width×width×width= 384
Answer=4.4267276788
1. (20 marks) A survey database shows that 20 percent of the adults in country A have been tested for HIV at some point in their life. (a) Suppose that an adult who has been tested for HIV at some point in his life is needed in a study. Some adults are randomly selected from the population of country A in the selection process until the one who has been tested for HIV is found. Let X be the number of adults selected in this process. Show that the cumulative probability P(X≤x)=1−0.8 x . (4 marks) (b) Using the formula of P(X≤x) in (a), find the probability that the number of adults selected in the process are: (i) Three, (ii) Less than five, (iii) Between five and nine, inclusive, (iv) More than five, but less than 10, (v) Six or more. (5 marks) (c) Find the mean and variance of the number of people selected in the above process. (3 marks) (d) Consider a simple random sample of 18 adults. Find the probability that the number of adults who have been tested for HIV in the sample would be: (i) Three, (ii) Less than five, (iii) Between five and nine, inclusive, (iv) More than five, but less than 10 , (v) Six or more. ( 5 marks) (e) Find the mean and variance of the number of people tested for HIV in the sample. (3 marks)
From the given data provided, the probability that number of adults selected in process are 3, less than 5, between 5 and 9, more than 5 but less than 10, 6 or more is 0.096, 0.41, 0.336, 0.232, 0.168 and mean of number of people tested for HIV is 3.6.
(a) The probability that an adult has not been tested for HIV is 1-0.20=0.80. Therefore, the probability that the first adult selected has not been tested for HIV is 0.80. The probability that the first and second adults selected have not been tested for HIV is 0.80 x 0.80=0.64. Continuing in this way, we see that the probability that X adults must be selected until one who has been tested for HIV is found is given by:
P(X≤x) = 1 - 0.80ˣ
(b) Using the formula from (a), we can find the probabilities as follows:
(i) P(X=3) = P(X≤3) - P(X≤2) = (1-0.80³) - (1-0.80²) = 0.096
(ii) P(X<5) = P(X≤4) = 1-0.80⁴ = 0.41
(iii) P(5≤X≤9) = P(X≤9) - P(X≤4) = (1-0.80⁹) - (1-0.80⁴) = 0.336
(iv) P(6≤X<10) = P(X≤9) - P(X≤5) = (1-0.80⁹) - (1-0.80⁵) = 0.232
(v) P(X≥6) = 1 - P(X≤5) = 1 - (1-0.80⁵) = 0.168
(c) To find the mean and variance of X, we first note that X follows a geometric distribution with parameter p=0.20. Therefore, the mean and variance of X are:
Mean of X = E(X) = 1/p = 1/0.20 = 5
Variance of X = Var(X) = (1-p)/p² = 0.8/0.04 = 20
(d) To find the probabilities for a random sample of 18 adults, we use the binomial distribution with parameters n=18 and p=0.20. The probabilities are:
(i) P(X=3) = (18 choose 3) x 0.20³ x 0.80¹⁵ = 0.236
(ii) P(X<5) = P(X≤4) = Σ(18 choose x) x 0.20ˣ x 0.80⁽¹⁸⁻ˣ⁾ for x=0 to 4 = 0.678
(iii) P(5≤X≤9) = Σ(18 choose x) x 0.20ˣ x 0.80⁽¹⁸⁻ˣ⁾ for x=5 to 9 = 0.286
(iv) P(6≤X<10) = Σ(18 choose x) x 0.20ˣ x 0.80⁽¹⁸⁻ˣ⁾ for x=6 to 9 = 0.207
(v) P(X≥6) = 1 - P(X≤5) = 1 - Σ(18 choose x) x 0.20ˣ x 0.80⁽¹⁸⁻ˣ⁾ for x=0 to 5 = 0.322
(e) The mean and variance of X for a sample of 18 adults are:
Mean of X = E(X) = n x p = 18 x 0.20 = 3.6
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f(x)=-2x^2+6x+1 what is the rate of change
The rate of change of the function f(x) = -2x² + 6x + 1 at x = 1 is approximately 0.302.
What is the definition of a function?
In mathematics, a function is a rule that assigns to each element in a set (called the domain) exactly one element in another set (called the range). In other words, a function takes an input value and produces a unique output value. The input value is usually represented by the variable x, while the output value is represented by the variable y or f(x).
Now,
The rate of change of a function is the slope of the line that connects any two points on the graph of the function. The slope of a line passing through two points (x1, y1) and (x2, y2) is given by:
slope = (y2 - y1)/(x2 - x1)
So to find the rate of change of the function f(x) = -2x² + 6x + 1, we need to choose two values of x and find the corresponding values of f(x), and then calculate the slope of the line passing through these two points.
Let's choose two values of x that are close to each other, say x1 = 1 and x2 = 1.01. Then, we have:
f(x1) = -2(1)² + 6(1) + 1 = 5
f(x2) = -2(1.01)² + 6(1.01) + 1 = 5.0302
Now, we can calculate the slope of the line passing through these two points:
slope = (f(x2) - f(x1))/(x2 - x1) = (5.0302 - 5)/(1.01 - 1) = 0.302
So,
the rate of change of the function f(x) = -2x² + 6x + 1 at x = 1 is approximately 0.302. Note that the rate of change of a function is not constant, but varies with the value of x.
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solve the system of equations -3x-5y=14 and 7x+7y=0 by combining the equations.
Answer:
x=7 & y=-7
Step-by-step explanation:
from the 2nd equation 7x+7y=0 we can get that
x=-y
substitute that into the first equation to get
3y-5y=14
-2y=14
y=-7
then
x=7
A city has 5 new houses for every 8 old houses. If there are 30 new houses in the city, how many old houses are there?
Answer: 48 old houses
Step-by-step explanation:
Ratio 5:8
Ratio 30:?
30/5=6
8 x 6= ...
48!!!
30:48
did this make sense??
i can’t figure this out out!! extra points
Step-by-step explanation:
as I just explained in your other posting of the same question :
y = cos(30) × 8 = sqrt(3)/2 × 8 = 4×sqrt(3).
so, the number in the green box is 4.
rick has 3x and helen has twice that amount they save 3 each per week what amount will be the sum of their money 4 weeks from now
Hence the amount of savings of Rick and Halens is = 9x+24.
When we write any linguistic statement in mathematics form called mathematical expression.
Rick has 3x to start with
Let w = the number of weeks he will save.
Savings = 3x + 3*w
Let w = 4
Savings = 3x+3*4
Savings = 3x + 12
Halen has twice Rick's amount,
Let w = the number of weeks she will save.
Savings=6x+3w
let w=4
savings=6x+12
Now we come to the question. It seems to want the total combining both of them.
Rick + Halen = 3x+12+6x+12 = 9x+24
Hence the amount of savings of rick and Halens is = 9x+24.
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Which two points would a line of fit go through to best fit the data? (6, 4) and (9, 1) (3, 5) and (10, 1) (1, 8) and (10, 1) (1, 5) and (7, 3)
The two points that a line of fit would go through to best fit the data are (3, 5) and (10, 1).
We need to find which pair of points have a line passing through them that best fits the data. One way to do this is to calculate the slope of the line passing through each pair of points and choose the pair of points with the slope closest to the average slope.
The slope of a line passing through two points [tex](x_1, y_1)[/tex] [tex](x_2, y_2)[/tex] is given by the formula:
slope = [tex]\frac{(y_2 - y_1)}{ (x_2 - x_1)}[/tex]
Using this formula, we can calculate the slopes of the lines passing through each pair of points:
Pair 1: slope = [tex]\frac{(1 - 4)}{(9-6)}[/tex] = -1
Pair 2: slope = [tex]\frac{(1 - 5)}{(10-3)}[/tex] = -0.67
Pair 3: slope = [tex]\frac{(1 - 8) }{(10-1)}[/tex] = -0.88
Pair 4: slope =[tex]\frac{ (3 - 5)}{(7-1)}[/tex] = -0.33
The average slope is:
average slope = [tex]\frac{(-1 + (-0.67) + (-0.88) + (-0.33))}{4}[/tex] = -0.72
The pair of points with the slope closest to the average slope is pair 2, with a slope of -0.67. Therefore, the two points that a line of fit would go through to best fit the data are (3, 5) and (10, 1).
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Fifty pairs of individuals playing in a bridge tournament have been seeded 1,. , 50. In the first part of the tournament, the 50 are randomly divided into 25 east-west pairs and 25 north-south pairs.
(a) What is the probability that x of the top 25 pairs end up playing east-west?
(b) What is the probability that all of the top five pairs end up playing the same direction?
(c) If there are 2n pairs, what is the pmf of X = the number among the top n pairs who end up playing east-west? What are E(X) and V(X)?
a .The probability that x of the top 25 pairs play east-west is: P(X = x) = (25 choose x) / (50 choose 25) , b. The probability that the top 5 pairs all play in the same direction is: P(all 5 play the same direction) = (1/2) * (24/49) * (23/48) * (22/47) * (21/46), c. The pmf of X is given by P(X = x) = [(n choose x) * (n choose n - x)] / [(2n choose n)], and the expected value and variance of X are E(X) = n/2 and V(X) = (n² - 1)/12.
P(X = x) = [(n choose x) * (n choose n - x)] / [(2n choose n)] yields the pmf of X. , and X's expected value and variance are, respectively, E(X) = n/2 and V(X) = (n² - 1)/12.
(a) Let X be the number of top 25 pairs that play east-west. Since there are 25 east-west pairs and 25 north-south pairs, the total number of ways to choose 25 pairs to play east-west is (50 choose 25) = 50! / (25! * 25!). Similarly, the total number of ways to choose x top pairs to play east-west is (25 choose x) * (25 choose 25 - x) = (25 choose x), since the remaining 25 pairs automatically play east-west. Therefore, the probability that x of the top 25 pairs play east-west is:
P(X = x) = (25 choose x) / (50 choose 25)
(b) The probability that the top pair plays east-west is 25/50 = 1/2. Once the top pair has been assigned a direction, the probability that the second pair plays in the same direction is 24/49, the probability that the third pair plays in the same direction is 23/48, and so on. Therefore, the probability that the top 5 pairs all play in the same direction is:
P(all 5 play the same direction) = (1/2) * (24/49) * (23/48) * (22/47) * (21/46)
(c) Let X be the number of top n pairs that play east-west, where there are 2n pairs total. Then X can take on values from 0 to n. To find the pmf of X, we can use the same method as in part (a):
P(X = x) = [(2n - n) choose x] / [(2n) choose n]
= [(n choose x) * (n choose n - x)] / [(2n choose n)]
The expected value of X is:
E(X) = sum[x * P(X = x), {x, 0, n}]
= sum[x * (n choose x) * (n choose n - x) / (2n choose n), {x, 0, n}]
Using the identity sum[x * (n choose x) * (n choose k - x), {x, 0, k}] = k * (n choose k), we can simplify this to:
E(X) = n/2
The variance of X is:
V(X) = E(X²) - E(X)²
= sum[x² * P(X = x), {x, 0, n}] - (n/2)²
= sum[x * (n choose x) * (n choose n - x) / (2n choose n), {x, 0, n}] - (n/2)²
= (n² - 1)/12
Therefore, the pmf of X is given by P(X = x) = [(n choose x) * (n choose n - x)] / [(2n choose n)], and the expected value and variance of X are E(X) = n/2 and V(X) = (n² - 1)/12, respectively.
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The product of two positive number is 108. If one one number is treble of other number, find those number
A central angle has a measure of 2. 3 radians and the subtended arc length is 12 cm. What is the radius of the circle to the nearest 10th
If A central angle has a measure of 2. 3 radians and the subtended arc length is 12 cm, then the radius of the circle is approximately 5.2 cm.
The formula relating the central angle, radius, and arc length of a circle is:
arc length = radius × central angle
We can use this formula to find the radius of the circle, given the central angle and arc length.
Substituting the given values, we get:
12 cm = r × 2.3 rad
Solving for r, we divide both sides by 2.3 rad:
r = 12 cm / 2.3 rad
Using a calculator, we get:
r ≈ 5.2174 cm
Rounding to the nearest tenth, we get:
r ≈ 5.2 cm
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In an obstacle course, participants climb to the top of a tower and use a zip line to travel across a mud pit. The zip line extends from the top of a tower to a point on the ground 48. 2 feet away from the base of the tower. The angle of elevation of the zip line is 33°. Estimate the length of the zip line to the nearest tenth of a foot
The estimated length of the zip line is 62.8 feet.
The length of a zip line can be estimated using the formula for the length of a side of a right triangle, which is the square root of the sum of the squares of the two shorter sides. In the case of the obstacle course, the two shorter sides are the height of the tower and the horizontal distance from the base of the tower to the point on the ground.
To calculate the length of the zip line, we first need to calculate the height of the tower. The angle of elevation of the zip line is 33°, so we can use trigonometry and the Law of Sines to calculate the height of the tower. The Law of Sines states that the ratio of the length of a side to the sine of its opposite angle is the same for all sides of the triangle. Since we know the angle of elevation (33°) and the horizontal distance (48.2 feet), we can calculate the height of the tower using the formula:
h = (48.2 * sin(33°)) / sin(90°)
h = 42.7 feet
Now we can calculate the length of the zip line using the formula for the length of a side of a right triangle:
[tex]L = sqrt(h^2 + d^2)L = sqrt(42.7^2 + 48.2^2)L = 62.8 feet[/tex]
Rounding to the nearest tenth of a foot, the length of the zip line is 62.8 feet.
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Examine the solution process below. If it is correct, select "The solution is correct." If incorrect, select the first equation in the solution process that is not true, Osuming that the prior equation is true. ► x + 4 = 2x + 11 3x + 4 = 11 3x = 15 x = 5 The solution is correct.
Answer: Yes the soultuion is corrrect
Step-by-step explanation:
Find the value of x in the regular octagon when each angle is represented by the expression (8x+23)°
The value of x in the regular octagon is 14°. The solution has been obtained by using arithmetic operations.
What are arithmetic operations?
All real numbers are claimed to be able to be described by the four basic operations, sometimes known as "arithmetic operations". Quotient, product, sum, and difference are the next four mathematical operations after division, multiplication, addition, and subtraction.
We are given that the measure of each angle is (8x + 23)°.
We know that the sum of angles of an octagon is 1080°.
So, using the arithmetic operation, we get
⇒ 8 * (8x + 23)° = 1080°
⇒ 64x + 184 = 1080°
⇒ 64x = 896°
⇒ x = 14°
Hence, the value of x in the regular octagon is 14°.
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What is the surface area of the three-dimensional figure represented by this net?
The net pattern has a square base of side lengths 3 inches, 3 inches, 3 inches and 3 inches are attached with four congruent triangles of height 8 inches.
Use the on-screen keyboard to type the correct number of square inches in the box below.
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The surface area of the three-dimensional figure represented by this net is 54 square inches, which is calculated by multiplying the area of the base (9 square inches) by the height of the four congruent triangles (8 inches).
The surface area of the three-dimensional figure represented by this net is 54 square inches. To calculate this, first we need to find the area of the base. The base is a square, with side lengths of 3 inches each. Therefore, the area of the base is 3 x 3 = 9 square inches. Next, we need to find the height of the four congruent triangles. The height is 8 inches. Finally, we can calculate the surface area by multiplying the area of the base (9 square inches) by the height of the four congruent triangles (8 inches). This gives us a total surface area of 54 square inches.
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Jaqi owes Katie$60and pays$35toward her debt. a. What percent of the debt has she paid? b. What percent is still owed? c. What is her debt now? d. If Jaqi pays Katie another$10toward her new debt, what pereent of her new debt is paid off?
a. Jaqi has paid 58.33% οf her debt.
b. Jaqi still οwes 41.67% οf her debt.
c. Jaqi's debt nοw is $25.
d. Jaqi wοuld have paid οff 40% οf her new debt.
What is a percentage?Percentage can be calculated by dividing the value by the tοtal value, and then multiplying the result by 100.
a. Tο find the percentage οf the debt that Jaqi has paid, we need tο divide the amοunt paid by the tοtal amοunt οwed and multiply by 100:
Percentage paid = (Amοunt paid / Tοtal amοunt οwed) x 100%
Percentage paid = (35 / 60) x 100%
Percentage paid = 58.33%
Sο Jaqi has paid 58.33% οf her debt.
b. Tο find the percentage still οwed, we can subtract the amοunt paid frοm the tοtal amοunt οwed, and then calculate the percentage:
Percentage still οwed = (Amοunt still οwed / Tοtal amοunt οwed) x 100%
Percentage still οwed = ((60 - 35) / 60) x 100%
Percentage still οwed = 41.67%
Sο Jaqi still οwes 41.67% οf her debt.
c. Tο find Jaqi's debt nοw, we simply subtract the amοunt paid frοm the οriginal debt:
Debt nοw = Tοtal amοunt οwed - Amοunt paid
Debt nοw = 60 - 35
Debt nοw = $25
Sο Jaqi's debt nοw is $25.
d. If Jaqi pays anοther $10 tοward her new debt οf $25, we can find the percentage paid as fοllοws:
Percentage paid = (Amοunt paid / Tοtal amοunt οwed) x 100%
Percentage paid = (10 / 25) x 100%
Percentage paid = 40%
Sο Jaqi wοuld have paid οff 40% οf her new debt.
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BRAINLIESTT ASAP! PLEASE HELP ME :)
Determine whether statement (3) follows from statements (1) and (2) by the Law of Detachment or the Law of Syllogism. If it does, state which law was used. If it does not, write invalid.
(1) If you use a pencil you can erase mistakes.
(2) If you can erase mistakes your paper will be neater.
(3) If you use a pencil your paper will be neater.
A. Invalid
B. Yes; Law of Detachment
C. Yes; Law of Syllogism
Statement (3) follows from statements (1) and (2) by the Law of Syllogism. So, the correct option c) which is Yes; Law of Syllogism
Here's the reasoning:
(1) If you use a pencil you can erase mistakes.
(2) If you can erase mistakes your paper will be neater.
Therefore, by the Law of Syllogism,
(3) If you use a pencil your paper will be neater.
The Law of Syllogism states that if we have two conditional statements (if A then B) and (if B then C), we can logically conclude a third conditional statement (if A then C). That's exactly what we've done here since statement (1) is the first conditional statement, statement (2) is the second conditional statement, and statement (3) is the conclusion that follows from applying the Law of Syllogism to the first two statements.
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Calculate how far a ball would be hit if it was hit at an angle of 25° and a velocity of 80 mph.
The distance that the ball was hit, considering that it was hit at an angle of 25° and a velocity of 80 mph, is given as follows:
d = 99.7 meters.
How to obtain the distance that the ball was hit?First we must obtain the time that the ball was in the air, and the equation is given as follows:
t = 2vy/g.
In which:
vy is the y-component of the velocity.g is the gravity.The y-component of the velocity is given as follows:
vy = vsin(y)
vy = 35.71 x sine of 25 degrees. (35.71 m/s = 80 mph)
vy = 15.1 m/s.
As the gravity is of 9.81 m/s², the time is given as follows:
t = 2 x 15.1/9.81
t = 3.08 s.
The distance is then given as follows:
d = Vxt.
d = 35.71 x cosine of 25 degrees x 3.08
d = 99.7 meters
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Number of Downloads by Quarter In the 3rd quarter, approximately how many more downioads were there of Starship than Flurry? 1.5 million 1.75 milion 2 million 2.25 miltion
The number of downloads of Starship than Flurry include the following: A. 1.5 million.
What is a line plot?In Mathematics and Statistics, a line plot can be defined as a type of graph that is used to graphically represent a data set above a number line, while using crosses, dots, or any other mathematical symbol.
Based on the data and information provided in the line plot shown in the image attached below, we can logically deduce the following parameters and key features:
Red line represent Starship.Purple line represent Flurry.At 3rd quarter, Starship = 3 million downloads.At 3rd quarter, Flurry = 1.5 million downloads.Next, we would calculate the difference between the downloads in the 3rd quarter for Starship and Flurry as follows;
Difference = 3 million downloads - 1.5 million downloads.
Difference = 1.5 million downloads.
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2. If twice a number is decreased by 13, the result is 9. What is the number?
Answer:
Let's start by translating the sentence into an equation using algebra.
Let's say the number is represented by "x".
According to the problem:
"Twice a number" can be written as "2x".
"If twice a number is decreased by 13" can be written as "2x - 13".
"The result is 9" can be written as "= 9".
Putting it all together, we get the equation:
2x - 13 = 9
Now we can solve for x:
2x = 22
x = 11
Therefore, the number is 11.