Answer: ($19.8, $20.8)
Step-by-step explanation:
Confidence interval for mean : [tex]\overline{x}\pm z^*\dfrac{\sigma}{\sqrt{n}}[/tex] , where [tex]\overline{x}[/tex] = Sample mean, n= sample size, [tex]\sigma[/tex] = population standard deviation, z* = two tailed critical z-value.
Given: [tex]\overline{x}[/tex] = $20.3
n= 2333
[tex]\sigma[/tex] = $11.3
For 98% confidence, z* = 2.326
Then, the98% confidence interval for population mean will be:
[tex]20.3\pm (2.326)\dfrac{11.3}{\sqrt{2333}}\\\\=20.3\pm (2.326)\dfrac{11.3}{48.3011387}\\\\=20.3\pm (0.544165224825)\\\\\approx 20.3\pm 0.5\\\\=(20.3-0.5,\ 20.3+0.5)\\\\=(19.8,20.8)[/tex]
Hence, the 98% confidence interval for the mean per capita income in thousands of dollars = (19.8, 20.8)
scientists are studying a population of 20 bugs and tracking the population, y, as it grows over time, t, in weeks. If the population grows by at least 6.1% each week, which system of inequalities represents the scenario?
Answer:
I am pretty sure it is
y >_ 20(0.061)^t
t >_ 0
Step-by-step explanation:
If a Ferris wheel takes 45 seconds to make a complete rotation, how many rotations will it complete in 3 hours?
Answer:240 rotations
Step-by-step explanation: 1 rotation/45 seconds * 60 seconds / minute * 60 minutes / hour * 3 hours = 3600*3/45 = 240 rotations
Find the distance between each pair of points in the coordinate plane.
(3,-2) and (2,-1)
Answer:
1.41
Step-by-step explanation:
Marc eats an egg sandwich for breakfast and a big burger for lunch every day. The egg sandwich has 250 calories. If Marc has 5,250 calories for breakfast and lunch for a week in total, how many calories are in one big burger.
Answer:
21 calouris
Step-by-step explanation:
5250/250
Answer:
500
Step-by-step explanation:
250 X 7 = 1750
5250 - 1750 = 3500
3500 divided by 7 =500
Simplify [tex]\frac{14^{15} }{14^{5} }[/tex]:
A. [tex]1^{3}[/tex]
B. [tex]1^{10}[/tex]
C. [tex]14^{3}[/tex]
D. [tex]14^{10}[/tex]
Answer:
The answer is D 14^10
Answer:
A
Step-by-step explanation:
mental math again 60x40x2
Answer:
the answer is 4800
Answer:
What is mental math?
Mental math is definitely what it sounds like—doing math in your head. But it’s also more nuanced than that. Being good at mental math tricks doesn’t mean that you’re able to solve 8974387 x 396 in your head instantly; while cool, that wouldn’t be very practical for daily life. So what does mental math mean?
It really just means being able to calculate in your head. It doesn’t mean you can solve every type of problem every time, nor is it a skill that you either “have” or “don’t have”; it’s a skill that you can learn, practice, and improve so that you can solve a bigger range of problems. And mental math certainly doesn’t have to be entirely in your head, either. Jotting down the numbers you need to remember to give you a head start (no pun intended), or writing down your solutions at each “step,” does not negate the “mental”-ness of the math.
Is mental math useful?
Ask this question again next time you’re trying to figure out a tip or doing any kind of construction or home improvement project! And, in addition to handy practical uses, knowing how to do mental math can also just keep your brain sharp and curb your reliance on calculators. Because, come on, doesn’t it feel good to reach for a calculator only to realize, “Wait, I don’t need it!” and figure out the answer in your head? (Spoiler: It does!) Not to mention knowing how to mentally solve small, simple math problems can save you some steps and help you out if you do need to solve a more complicated, difficult problem. There are always going to be some math problems that it would be silly to not solve with a calculator, but, yes, mental math is useful. And if you’re wondering if math itself is useful, math lessons you’ll actually use in real life.
Step-by-step explanation:
Mai says that -8 > -4 . Do you agree with her? Explain or show your reasoning.
Answer:
No
Step-by-step explanation:
-8 is less than -4. Negative numbers reverse the logic of positive ones: since positive 8 is more than positive 4, negative 8 is less than negative 4.
Plz help Plz help
Ella played a math game and had the five cards shown.
7 0 -4 -10
Her score was the sum of the numbers on these five cards. What was Ella’s score?
3
⊝
23
−5
⊝
Not here
Answer:
-7 (Not here)
Step-by-step explanation:
1. A negative plus a negative equals a negative/ a negative minus a positive equals a negative so: -10 -4 = -14
2. -14 + 7 = -7 so your answer is -7 and it's not an answer choice so you would select "Not here"
What is the slope of a line perpendicular to the line whose equation is
2x – 2y = 20.
Answer:
-1
Step-by-step explanation:
Solve for y into y=mx+b
2x-2y=20
-2y=-2x+20
y=(-2x+20)/-2
y=x-10
the slope is m, so it’s 1
A line perpendicular to that would be -1
The formula κ(x)= f′′(x) 1+f′(x)23/2 expresses the curvature of a twice-differentiable plane curve as a function of x. Use this formula to find the curvature function of the following curve. f(x)=−5x2 The curvature function is κ(x)=nothing.
Answer:
K(x) = [tex]\frac{-10}{[1 + (-10x)^2]^{\frac{3}{2} } }[/tex] ( curvature function)
Step-by-step explanation:
considering the Given function
F(x) = [tex]-5x^2[/tex]
first Determine the value of F'(x)
F'(x) = [tex]\frac{d(-5x^2)}{dy}[/tex]
F'(x) = -10x
next we Determine the value of F"(x)
F"(x) = [tex]\frac{d(-10x)}{dy}[/tex]
F" (x) = -10
To find the curvature function we have to insert the values above into the given formula
K(x) [tex]= \frac{|f"(x)|}{[1 +( f'(x)^2)]^{\frac{3}{2} } }[/tex]
K(x) = [tex]\frac{-10}{[1 + (-10x)^2]^{\frac{3}{2} } }[/tex] ( curvature function)
The two lines graphed below are not parallel. How many solutions are there to
the system of equations?
Answer:
I think it might be zero
Step-by-step explanation:
you might want to look into this all the way beforyou trust put it into*
Which series of transformations would result in a figure that is congruent to the triangle ABC?
rotation of 180' clockwise about the origin and then dilation with a scale factor of -1, centered at the origin
rotation of 180' clockwise about the origin and then dilation with a scale factor of 2, centered at the origin
reflection across the line y ox and then dilation with a scale factor of -3, centered at the origin
translation 3 units to right and then dilation with a scale factor of 3, centered at the origin
Answer: rotation of 180' clockwise about the origin and then dilation with a scale factor of -1, centered at the origin
Step-by-step explanation:
Two triangles are congruent if all the corresponding angles are equal, and if the corresponding side lengths are equal.
Now, this means that if we have a given triangle, and we apply a dilation/contraction, then the resultant triangle will have different side lengths than the initial triangle, then those two triangles can not be congruent.
So we can already discard all the options with dilations.
Now, remember how the dilation works.
If we have a point that is at a distance L of the origin, and we do a dilation of scale factor K centered at the origin, then the new distance of the point and the origin will be K*L.
Notice that if the scale factor is equal to 1, then there is no change.
In the options, we have one where the scale factor is -1.
The minus sign means that will cause the enlargement to appear on the other side of the center of enlargement. But the scale factor still is of absolute value 1, so it will not change anything.
Then the only option that not dilates the triangle is:
Rotation of 180' clockwise about the origin and then dilation with a scale factor of -1, centered at the origin
So this is the only transformation that results in a figure congruent to the triangle ABC
Compare: -7 -4
PLEASE HELP ME!
3.A normal bus carries x passengers.
A large bus will carry twice as many passengers than the normal bus
A small bus will carry 8 passengers less than the normal bus.
Altogether the buses carry 128 passengers.
(a) Form a simplified equation in terms of x
Answer: A) 4x -8 = 128
Step-by-step explanation:
We will represent the amount that the normal bus carries by n= x
We will represent the amount that the large bus carries by l = 2x
We will also represent the amount that the small bus carries by s = x-8
Now add them to equal to 128.
x + 2x + x -8 = 128
4x -8 = 128
What is the equation in slope-intercept form of the line that passes through the points (−12, −4) and (4, 8)?
A. y = −43 − 20
A. , y = −43 − 20
B. y = 43 − 12
B. , y = 43 − 12
C. y = −0.75 − 13
C. , y = −0.75 − 13
D. y = 0.75x +5
D. , y = 0.75x +5
Answer:
Choice D. [tex]y = 0.75\, x + 5[/tex].
Step-by-step explanation:
The general equation for the slope-intercept form of a line in a cartesian plane is [tex]y = m\, x + b[/tex], where:
[tex]m[/tex] is the slope of the line, and[tex]b[/tex] is the [tex]y[/tex]-intercept of the line. (The [tex]y\![/tex]-intercept of a line in a cartesian plane is the [tex]y\!\![/tex]-coordinate of the point where the line intersects the [tex]\! y \![/tex]-axis.)Start by finding the value of [tex]m[/tex]. The slope of a line is equal to its rise-over-run. For the two points in this question:
The "rise" is the [tex]y[/tex]-coordinate of the first point minus that of the second: [tex]\text{rise} = (-4) - 8 = -12[/tex].The "run" is the [tex]x[/tex]-coordinate of the first point minus that of the second. The order of these two points should stay the same: [tex]\text{run} = (-12) - 4 = -16[/tex].Calculate the slope of this line:
[tex]\displaystyle m = \text{slope} = \frac{\text{rise}}{\text{run}} = \frac{-12}{-16} = 0.75[/tex].
The equation of the line becomes:
[tex]y = \underbrace{0.75}_{m}\, x + b[/tex].
Substitute the coordinates of either of the two points to find [tex]b[/tex]. For example, for the first point [tex](12, -4)[/tex], substitute in the following:
[tex]x = -12[/tex], and[tex]y = -4[/tex].The equation becomes:
[tex]-4 = 0.75 \times (-12) + b[/tex].
Solve for the value of [tex]b[/tex]:
[tex]b = 5[/tex].
Hence, the slope-intercept form of this line shall be:
[tex]y = 0.75\, x + 5[/tex].
Mr. Clopu buys an 18-month CD that pays 434% simple interest for $5,000. Find the value of the CD at the end of its term.
Answer:
FV= $5,325.8
Step-by-step explanation:
Giving the following information:
Mr. Clopu buys an 18-month CD that pays 4.34% simple interest for $5,000.
To calculate the future value, we need to use the following formula:
FV= (P*r*t) + P
P= $5,000
r= 0.0434/12= 0.00362
t= 18
FV= [(5,000*0.00362)*18] + 5,000
FV= $5,325.8
The value of the CD at the end of its term is $39,060
Given:
Time = 18 month
Principal = $5000
Interest rate = 434%
Future value = ?
Future value = Principal × Rate × Time
= 5,000 × 434% × 18
= 5000 × 434/100 × 18
= 5000 × 4.34 × 18
= 39,060
Therefore, the value of the CD at the end of its term is $39,060
Read more:
https://brainly.com/question/12164462
PLSSSS HELLPPPP MEEEEEEE ASAPPPP I WIILL GIVE BRAINLIEST!!!!!!!!! PLS SHOW WORK STEP BY STEP
Answer:
y = -3x + 3
Step-by-step explanation:
Slope = -3
y-intercept = 3
Substitute values into slope intercept form :
y=mx + b
Where :
m= Slope
b = y-intercept
[tex]y = - 3x + 3[/tex]
Solve the following equation algebraically. Show your work.
6=x+23
Answer: 23+x=6
-23 -23
1x/1 -17/1
x=-17
Step-by-step explanation:
Answer:
Rearrange the equation by subtracting what is to the right of the equal sign from both sides of the equation :
-6*x-(23)=0
Step by step explanation :
Pulling out like terms
Pull out like factors :
-6x - 23 = -1 • (6x + 23)
Solving a Single Variable Equation:
2.1 Solve : -6x-23 = 0
Add 23 to both sides of the equation :
-6x = 23
Multiply both sides of the equation by (-1) : 6x = -23
Divide both sides of the equation by 6:
x = -23/6 = -3.833
Therfor the answer is : x = -23/6 = -3.833
If the quarter note equals one beat, how many beats would this note be worth?
Answer:
4 beats
Step-by-step explanation:
that is a whole note and 4 quarters are equal to one whole
if you can help i’d appreciate it
Answer:
B- 44
Step-by-step explanation:
87.5 divided by 2 is 43.75. Since it's a square wall, the length and height are both the same, and since length times height is area, if you divide the area by two, you can get a length of one of the sides. Out of all the answers, 44 is the closest to 43.75.
hope this helped! -brooke :))
Help meeee pleaseeeeee
Answer:
B.
Step-by-step explanation:
I think its B because the Y comes before the slope
3x-(-54x)=45= whats the sum
Answer:
x= 15/19 = 0.789
Step-by-step explanation:
Answer: 0.789 is the correct answer plz brainliest big brother
If 12 roses cost 30.4 how much will 18 roses cost?
Answer:
45.6
Step-by-step explanation:
We can write a proportion to solve
12 roses 18 roses
------------ = -----------
30.4 x
Using cross products
12x = 30.4 * 18
12x=547.2
Divide each side by 12
12x/12 = 547.2/12
x = 45.6
Barb’s Grandma is always creating math problems for her to solve. In one problem she gave Barb a store receipt that listed 72 identical items, each the same price, for a total cost of $*67.9* Barb’s grandma covered the first and last digits of the total price on the receipt with stars. Determine the value of the digits that Barb’s Grandma covered.
9514 1404 393
Answer:
367.92
Step-by-step explanation:
72 = 9·8
In order for the total cost to be divisible by both 8 and 9, it must meet a couple of requirements:
The sum of the digits must be divisible by 9. The last three digits must be divisible by 8.In order for the sum of digits to be divisible by 9, the first and last digits must total 5 or 14. (The total of existing digits is 22. The sum needs to be 27 or 36.)
In order for the last three digits to be divisible by 8, the last digit must be 2*. So, the first digit must be 5-2=3.
The first digit is 3; the last digit is 2.
The total cost is 367.92. Each item price is 367.92/72 = $5.11.
_____
* 790/8 = 98.75, so (790 + 2)/8 will be 99. 792 is the only number starting with 79 that is divisible by 8.
PLEASE HELP!!! i’ll give brainliest
Answer:
x = [tex]\sqrt{164[/tex]
Step-by-step explanation:
In order to find the hypothenuse, you need to do [tex]8^{2} + 10^{2}[/tex]. Which equals 164. Therefore, since [tex]a^{2} +b^{2} =c^{2}[/tex], a=8, b=10, and c=[tex]\sqrt{164[/tex].
Piper and her children went into a movie theater and she bought $59.50
bags of popcorn and candies. Each bag of popcorn costs $8.50 and each candy costs
$4.25. She bought 8 more candies than bags of popcorn. Graphically solve a system
of equations in order to determine the number of bags of popcorn, x, and the number
of candies, y, that Piper bought.
6 candy boxes
Step-by-step explanation :
Since they both bought their own popcorn that means they both spent $8 on popcorn making that a total of $16. Therefore we now only need to find one variable which is the number of candy boxes that they bought in order to reach the $25 total that they spent. This variable can be represented as x in the following algebraic equation.
(2*8) + 1.50x = 25
16 + 1.50x = 25 ... subtract 16 from both sides
1.50x = 9 ... divide both sides by 1.50
x = 6
Finally, we can see that Billy and Tommy bought a total of 6 candy boxes.
Answer:
This is the answer on Delta Math
Step-by-step explanation:
Which 2 subjects are 2 unit apart
Answer:
I believe that your answer is C and Moon.
Yousef typed a 36-word paragraph in 23 minute. What is his typing speed, in words per minute?
Answer:
1.5652173913 words per minute.
Step-by-step explanation:
When you divide 36 words/ 23 minutes, you get 1.5652173913.
Multiply -2.6 (-3.4)=
Answer:
8.84
Step-by-step explanation:
Answer:
8.84
Step-by-step explanation:
An airplane is flying overhead at a constant elevation of 4090 ft. A person is viewing the plane from a position 3010 ft from the base of a radio tower. The airplane is flying horizontally away from the person. If the plane is flying at the rate of 700 ft/s, at what rate is the distance between the person and the plane increasing when the plane passes over the radio tower
Answer:
415 ft/s
Step-by-step explanation:
I've attached a diagram showing the triangle formed between the plane, the person and the radio tower.
From the attached diagram, x represents the position between the person and the position on the ground directly below the airplane while s represents the distance between the person and the plane.
The constant elevation remains 4090 ft while the value of x and s varies with time.
Thus, x varies with respect to time as dx/dt while s varies with respect to time as ds/dt.
Now, we are told that the plane is flying at the rate of 700 ft/s. This means that; dx/dt = 700 ft/s
Now we want to find the rate at which the distance between the person and the plane is increasing when the plane passes over the radio tower.
This means that we want to find ds/dt when x = 3010 ft
From pythagoras theorem if x = 3010 ft and the Elevation remains 4090 ft, we can find s as;
s = √(4090² + 3010²)
s = √25788200
s ≈ 5078.21 ft
Since we want to find ds/dt at x = 3010 ft, from the diagram, we can say from pythagoras theorem that;
x² + 4090² = s²
Differentiating x and s with respect to t, we have;
2x(dx/dt) = 2s(ds/dt)
2 will cancel out to give;
x(dx/dt) = s(ds/dt)
ds/dt = (x/s)(dx/dt)
Plugging in 700 for dx/dt, 3010 for x and 5078.21 for s, we have;
ds/dt = (3010/5078.21) × 700
ds/dt ≈ 415 ft/s