INFORMATION:
We know that:
- John sells plain cakes for $8 and decorated cakes for $12.
- On a particular day, John started with a total of 100 cakes, and sold all but 4.
- His sales that day totaled $800.
And we must find the number of plain cakes and decorated cakes that he sold that day.
STEP BY STEP EXPLANATION:
To find them, we can represent the situation using a system of equations
[tex]\begin{cases}x+y={100-4...(1)} \\ 8x+12y={800...(2)}\end{cases}[/tex]Where, x represents the number of plain cakes that he sold and y represents the number of decorated cakes that he sold.
Now, we must solve the system:
1. We must multiply the equation (1) by -8
[tex]\begin{gathered} -8(x+y)=-8(100-4) \\ -8x-8y=-768...(3) \end{gathered}[/tex]2. We must add equations (2) and (3)
[tex]\begin{gathered} 8x+12y=800 \\ -8x-8y=-768 \\ ---------- \\ 0x+4y=32 \\ \text{ Simplifying, } \\ 4y=32...(4) \end{gathered}[/tex]3. We must solve equation (4) for y
[tex]\begin{gathered} 4y=32 \\ y=\frac{32}{4} \\ y=8 \end{gathered}[/tex]4. We must replace the value of y in equation (1) and then solve it for x
[tex]\begin{gathered} x+8=100-4 \\ x=100-4-8 \\ x=88 \end{gathered}[/tex]So, we found that x = 88 and y = 8.
Finally, John sold 88 plain cakes and 8 decorated cakes.
ANSWER:
He sold 88 plain cakes and 8 decorated cakes that day.
I need help with this
Write the slope-intercept form of the equation of the line graphed on the coordinate plane.
The slope-intercept form is:
[tex]y\text{ = mx + b}[/tex]We have to find these coefficients. To do that we have to choose two points in the graph and apply the following formula. I will use (0,1) and (-1,-1). The formula is:
[tex]y-yo\text{ = m(x-xo)}[/tex]The formula of the coefficient 'm' is:
[tex]m\text{ = }\frac{y2-y1}{x2-x1}[/tex]Let's substitute the points into the formula above to find the value of m. Then we use one of the points to find the slope-intercept form of the equation:
[tex]m\text{ = }\frac{-1-1}{-1-0}=2[/tex]Applying it to the second equation using the point (0,1):
[tex]y-1=2(x-0)[/tex][tex]y=2x+1[/tex]Answer: The slope-intercept form of the equation will be 2x+1.
Write the equation for a parabola with a focus at (1,2) and a directrix at y=6
Solution:
Given:
[tex]\begin{gathered} focus=(1,2) \\ directrix,y=6 \end{gathered}[/tex]Step 1:
The equation of a parabola is given below as
[tex]\begin{gathered} y=\frac{1}{4(f-k)}(x-h)^2+k \\ (h,f)=focus \\ h=1,f=2 \end{gathered}[/tex]Step 2:
The distance from the focus to the vertex is equal to the distance from the vertex to the directrix:
[tex]\begin{gathered} f-k=k-6 \\ 2-k=k-6 \\ 2k=2+6 \\ 2k=8 \\ \frac{2k}{2}=\frac{8}{2} \\ k=4 \end{gathered}[/tex]Step 3:
Substitute the values in the general equation of a parabola, we will have
[tex]\begin{gathered} y=\frac{1}{4(f-k)}(x-h)^{2}+k \\ y=\frac{1}{4(2-4)}(x-1)^2+4 \\ y=-\frac{1}{8}(x-1)^2+4 \\ \end{gathered}[/tex]By expanding, we will have
[tex]\begin{gathered} y=-\frac{1}{8}(x-1)^{2}+4 \\ y=-\frac{1}{8}(x-1)(x-1)+4 \\ y=-\frac{1}{8}(x^2-x-x+1)+4 \\ y=-\frac{1}{8}(x^2-2x+1)+4 \\ y=-\frac{x^2}{8}+\frac{x}{4}-\frac{1}{8}+4 \\ y=-\frac{x^2}{8}+\frac{x}{4}-\frac{1+32}{8} \\ y=-\frac{x^2}{8}+\frac{x}{4}+\frac{31}{8} \end{gathered}[/tex]Hence,
The final answer is
[tex]\begin{gathered} \Rightarrow y=-\frac{x^{2}}{8}+\frac{x}{4}+\frac{31}{8}(standard\text{ }form) \\ \Rightarrow y=-\frac{1}{8}(x-1)^2+4(vertex\text{ }form) \end{gathered}[/tex]Question 11 5 pts Find the value of x. Round to the nearest tenth. х 329 12. Not drawn to scale a. 10.2 b. 14.3 C. 10.4 d. 14.2
Explanation
Step 1
Let
angle= 32
hypotenuse=x
adjacent side=12
so, we need a function that relates angel, hypotenuse and adjacent side
[tex]\text{cos}\emptyset=\frac{adjacent\text{ side}}{\text{hypotenuse}}[/tex]replace,
[tex]\begin{gathered} \text{cos}\emptyset=\frac{adjacent\text{ side}}{\text{hypotenuse}} \\ \text{cos32}=\frac{12}{\text{x}} \\ \text{Multiply both sides by x} \\ x\cdot\text{cos32}=\frac{12}{\text{x}}\cdot x \\ x\cdot\text{cos32}=12 \\ \text{divide both sides by cos 32} \\ \frac{x\cdot\text{cos32}}{\cos \text{ 32}}=\frac{12}{cos\text{ 32}} \\ x=14.15 \\ rounded \\ x=14.2 \end{gathered}[/tex]so, the answer is
[tex]d)x=14.2[/tex]I hope this helps you
pleaseee help meeee For questions 9 - 10, answer the question about inverses. 9. The function m(d) below relates the miles Bob can drive his rental car and the numbers of dollars it will cost. 10. The function a(h) below relates the area of a triangle with a given base 7 and the height of the triangle. It takes as input the number of dollars spent and returns as output the number of miles. It takes as input the height of the triangle and returns as output the of the triangle. m(d) = 40(d- 35) ain= Write the equation that represents the inverse function, d(m), which takes the number of miles driven, m, as input and returns the number of dollars owed, d. Write the equation that represents inverse function, h(a), which takes triangle's area as input and returns height of the triangle.
First problem:
Find the inverse of the function
m = 40 (d - 35)
Recall that for the inverse function we need to solve for d in terms of m (reverse the dependence), so we proceed to isolate d on the right hand side of the equation:
divide both sides by 40
m/40 = d - 35
now add 35 to both sides:
m/40 + 35 = d
The inverse function (dollars in terms of miles) is given then by:
d(m) = 1/40 m + 35
Second problem:
a = 7 * h / 2
in order to find the inverse function (as h in terms of a) we solve for h on the right hand side of the equation as shown below:
multiply both sides by 2:
2 * a = 7 * h
now divide both sides by 7 in order to isolate h on the right
2 a / 7 = h
So our inverse function of height in terms of area is given by:
h(a) = (2 a) / 7
Given l//m//n find the value of x (5x)° (6x-13)°
The line l and the transversal line are intersecting each other.
So, from the theorem of Vertically Opposite angle
A pair of vertically opposite angles are always equal to each other.
thus, 5x = 6x - 13
Simplify the expression :
5x = 6x -13
6x-5x =13
x = 13
Answer : x = 13
are f(x) and g(x) inverse functions across the domain (5, + infinity)
Given:
[tex]\begin{gathered} F(x)=\sqrt{x-5}+4 \\ G(x)=(x-4)^2+5 \end{gathered}[/tex]Required:
Find F(x) and G(x) are inverse functions or not.
Explanation:
Given that
[tex]\begin{gathered} F(x)=\sqrt{x-5}+4 \\ G(x)=(x-4)^{2}+5 \end{gathered}[/tex]Let
[tex]F(x)=y[/tex][tex]\begin{gathered} y=\sqrt{x-5}+4 \\ y-4=\sqrt{x-5} \end{gathered}[/tex]Take the square on both sides.
[tex](y-4)^2=x-5[/tex]Interchange x and y as:
[tex]\begin{gathered} (x-4)^2=y-5 \\ y=(x-4)^2+5 \end{gathered}[/tex]Substitute y = G(x)
[tex]G(x)=(x-4)^2+5[/tex]This is the G(x) function.
So F(x) and G(x) are inverse functions.
[tex]\begin{gathered} G(x)-5=(x-4)^2 \\ \sqrt{G(x)-5}=x-4 \\ x=\sqrt{G(x)-5}+4 \end{gathered}[/tex]Final Answer:
Option A is the correct answer.
45 + 54 = 99 times ( ) + ( )
a) You have to find the greatest common factor for the values 45 and 54
To do so you have to determine the factors for each value and determine the highest value both numbers are divisible for.
Factors of 45 are
1, 3, 5, 9, 15, 45
Factors of 54 are
1, 2, 3, 6, 9, 18, 27, 54
The greatest common factor is 9, this means that you can divide both numbers by 9 and the result will be an integer:
[tex]\frac{45}{9}=5[/tex][tex]\frac{54}{9}=6[/tex]b) Given the addition
[tex]45+54[/tex]You have to factorize the adition using the common factor.
That is to "take out" the 9 of the addition, i.e. divide 45 and 54 by 9 and you get the result (5+6) but for this result to be equvalent to the original calculation, you have to multiply it by 9
[tex]45+54=9(5+6)[/tex]How can you use transformations to verify that the triangles are similar?
We need to know about congruency to solve the problem. Two pairs of congruent angles prove that the triangles are similar.
We can define similarity of two geometrical objects on a plane as possibility to transform one into another using dilation optionally combined with congruent transformations of parallel shift, rotation and symmetry. We need to use transformation to verify whether the triangles in the diagram are similar. The two triangles have a common angle D and angles ABD and ECD are equal. Thus we can say that we have two pairs of congruent angles in the two triangles, so the two triangles are similar.
Therefore the triangles are similar since they have two pair of congruent angles.
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(statistics) solve part A, B, and C in the question on the picture provide, in 1-3 complete sentences each.
(a.) First let's define the terms;
Population - it is the pool of individual in which a statistical sample is drawn.
Parameter - it is a measure of quantity that summarizes or describes a Population.
Sample - is a smaller and more managable version of a group or population.
Statistics - same with parameter but rather than the population, it summarizes or describes
the sample.
Now that we know the definitions we can now answe the letter a;
Population: Students
Parameter: the population portion of the new students that like the new healthy choices (p)
Sample: 150 students
Statistics: estimated propotion of the students that like the new healthy choices (p-hat)
(b) P-hat = 0.6267 simply means that 62.67% of the 150 sample students like the new healthy choices.
(c) The answer for that is NO, because the simulated propotion which is shown by the graph seems to be equally distributed below and above 0.7. To support the claim of the manager most of the dots should be below 0.7 to show support to his claim that 70% of the new students like the new healthy choices.
Draw the angle 0=-pi/2 in standard position find the sin and cos
An angle in standard position has the vertex at the origin and the initial side is on the positive x-axis.
Thus, the initial side of the angle is:
Now, half the circumference measures pi, thus, pi/2 is a quarte of the circumference. As we want to find the angle -pi/2, then we need to rotate the terminal side clockwise:
Find the sine and the cosine.
The sine and the cosine in the unit circle are given by the coordinates as follows:
[tex](\cos\theta,\sin\theta)[/tex]As can be seen in the given unit circle, the terminal side is located at:
[tex](0,-1)[/tex]Thus, the values of cosine and sine are:
[tex]\begin{gathered} \cos\theta=0 \\ \sin\theta=-1 \end{gathered}[/tex]Give the following numberin Base 2.7710 = [ ? ] 2Enter the number that belongs in the green box.
To convert a number on base 10 to binary(base 2), we use the following steps
1 - Divide the number by 2.
2 - Get the integer quotient for the next iteration.
3 - Get the remainder for the binary digit.
4 - Repeat the steps until the quotient is equal to 0.
Using this process in our number, we have
Then, we have our result
[tex]77_{10}=1001101_2[/tex]A car is traveling at a speed of 70 kilometers per hour. What is the car's speed in miles per hour? How many miles will the car travel in 5 hours? In your computations, assume that 1 mile is equal to 1.6 kilometers. Do not round your answers.
What is the car's speed in miles per hour?
Let's make a conversion:
[tex]\frac{70\operatorname{km}}{h}\times\frac{1mi}{1.6\operatorname{km}}=\frac{43.75mi}{h}[/tex]How many miles will the car travel in 5 hours?
1h---------------------->43.75mi
5h---------------------> x mi
[tex]\begin{gathered} \frac{1}{5}=\frac{43.75}{x} \\ x=5\times43.75 \\ x=218.75mi \end{gathered}[/tex]What's the divisor, dividend, Quotient, and reminder in a long divison problem
In a long division problem, say 8/5:
[tex]\frac{8}{5}\text{ is the quotient}[/tex]• 8 is the divisor
,• 5 is the dividend
[tex]\frac{8}{5}=1\frac{3}{5}[/tex]• 3 is the remainder.
if Maria collected R rocks and Javy collected twice as many rocks as Maria and Pablo collected 5 less than Javy. What is the sum of rocks collected by Pablo and Maria?
This problem deals with the numbers expressed in a more general way: letters or variables
That belongs to Algebra
We know Maria collected R rocks. Let's put this in a separate line:
M = R
Where M is meant to be the number of rocks collected by Maria
Now we also know Javy collected twice as many rocks as Maria did. Thus, if J is that variable, we know that
J = 2R
Pablo collected 5 less rocks than Javy. This is expressed as
P = J - 5
or equivalently:
P = 2R - 5
since J = 2R, as we already stated
We are now required to calculate the sum of rocks collected by Pablo and Maria.
This is done by adding P + M:
P + M = (2R - 5) + (R)
We have used parentheses to indicate we are replacing variables for their equivalent expressions
Now, simplify the expression:
P + M = 2R - 5 + R
We collect the same letters by adding their coefficients:
P + M = 3R - 5
Answer: Pablo and Maria collected 3R - 5 rocks together
Finding the area of unusual shapes
The shape in question is a composite shape.
It comprises two(2) shapes which are a triangle and a semi-circle.
The area of the shape is the sum of the area of the triangle and that of the semi-circle
The area of the triangle is:
[tex]A_{triangle}=\frac{1}{2}\times base\times height[/tex][tex]\begin{gathered} \text{Base of the triangle =}6\text{ yard} \\ Height\text{ of the triangle= 4 yard} \end{gathered}[/tex]Thus,
[tex]\begin{gathered} A_{triangle}=\frac{1}{2}\times6\times4 \\ A_{triangle}=12\text{ yards} \end{gathered}[/tex]Area of the Semi-circle is:
[tex]A_{semi-circle}=\frac{\pi\times r^2}{2}[/tex][tex]\begin{gathered} \text{Diameter of the circle=6 yard} \\ \text{Radius}=\frac{Diameter}{2} \\ \text{Radius}=\frac{6}{2}=3\text{ yard} \end{gathered}[/tex][tex]\begin{gathered} A_{semi-circle}=\frac{3.14\times3^2}{2} \\ A_{semi-circle}=\frac{28.26}{2} \\ A_{semi-circle}=14.13\text{ yard} \end{gathered}[/tex]Hence, the area of the composite shape is:
[tex]\begin{gathered} \text{Area of the triangle + Area of the semi-circle} \\ 12+14.13=26.13\text{ yard} \end{gathered}[/tex]how do you find a point slope in geometry
see explanation below
Explanation:
To find the point slope form of an equation, we will apply the formula:
[tex]y-y_1=m(x-x_1)[/tex]Given two points, we will be able to find the slope = m
for example: (1, 2), (2, 4)
m = slope = change in y/ change in x
m = (4-2)/(2-1)
m = 2/1
m = 2
Then, we will pick any of the points and insert into the formula for the point slope.
Let's assume we are using point (1, 2) = (x1, y1)
inserting into the formula together with the slope gives:
y - 2 = 2(x - 1)
The above is a point slope for the points given.
help meeeeeeeeee pleaseee !!!!!
The addition of the given functions f(x) and g(x) is equal to the expression x^2+ 3x + 5
Composite function.Function composition is an operation that takes two functions, f and g, and creates a function, h, that is equal to g and f, such that h(x) = g.
Given the following functions
f(x) = x^2 + 5
g(x) = 3x
We are to determine the sum of both functions as shown;
(f+g)(x) = f(x) + g(x)
Substitute the given functions into the formula
(f+g)(x) = x^2+5 + 3x
Write the expression in standard form;
(f+g)(x) = x^2+ 3x + 5
Hence the sum of the functions f(x) and g(x) is equivalent to x^2+ 3x + 5
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find the solution to the following system by substitution x + y = 20 y = 3x 8
Based on the substitution method, the solution of the system of the equation is x = 3 and y = 17.
Substitution method:
Substitution method is the way of finding the value of any one of the variables from one equation in terms of the other variable.
Given,
Here we have the system of equations
x + y = 20
y = 3x + 8
Now we need to find the solutions for these equation using the substitution method.
From the given details we know that the value of y is defined as 3x + 8.
So, we have to apply these value on the other equation in order to find the value of x,
x + (3x + 8) = 20
4x + 8 = 20
4x = 20 - 8
4x = 12
x = 3
Now apply the value of x into the other equation in order to find the value of y,
y = 3(3) + 8
y = 9 + 8
y = 17
Therefore, the solution of the equation is x = 3 and y = 17.
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how do you find the sale price of the item if original price $71 and mark down to 34% the sale price is
Answer:
The sale price is $46.86
Explanation:
Given an original price of $71, and a markdown of 34%
The sale price is:
$71 - (34% of $71)
= $71 - (0.34 * $71)
= $71 - $24.14
= $46.86
Answer:
The sale price is $46.86
Explanation:
Given an original price of $71, and a markdown of 34%
The sale price is:
$71 - (34% of $71)
= $71 - (0.34 * $71)
= $71 - $24.14
= $46.86
May I please get help with describing each or the math problems
From the given traingles, let's select the correct statements.
(a) Select all that describe BD.
Here, the line BD divides angle B into 2 equal parts. It means BD bisects ∠D.
An angle bisector is a line that divides an angle into two equal angles.
Hence, we can say BD is an angle bisector of ∠B.
(b) Select all that describe HI.
Since m∠FIH is a right triangle, it means ∠HIG is also a right triangle.
Also, the line HI originates from the vertex.
Since. the it forms a right angle, we can say HJ is an altitude of the triangle FGH.
Hence, HJ is an altitude of ΔFGH.
(c) Select all that describe MN.
Here, we can see that line MN divides the line segment KL into two equal parts, it means that point M is the median of the line segment KM and the pperpendicular bisector of line segment KL.
A perpendicular bisector is a line segment that divides another line segement into two equal parts.
KM = LM
Hence, MN is the perpendicular bisector of KL.
ANSWER:
• (a) Angle bisector of ∠B.
,• (b) Altitude of ΔFGH.
,• (c) Perpendicular bisector of KL.
The Leaning Tower of Pisa
was completed in 1372 and
makes an 86* angle with
the ground. The tower is
about 57 meters tall, measured
vertically from the ground
to its highest point. If you
were to climb to the top and
then accidently drop your
keys, where would you
start looking for them?
How far from the base of.
the tower would they land?
The distance where the keys would drop from the base is 3.5m
Calculation far from the base of tower?Height of the tower = 57m
Angle it makes to the ground = 86°
To solve this question, you have to understand that the tower isn't vertically upright and the height of the tower is different from the distance from the top of the tower to the ground.
The tower makes an angle 86° to the ground and that makes it not vertically straight because a vertically straight building is at 90° to the ground.
The distance from where the keys drop to the base of the tower can be calculated using
We have to use cosθ = adjacent / hypothenus
θ = 86°
Adjacent = ? = x
Hypothenus = 57m
Cos θ = x / hyp
Cos 86 = x / 57
X = 57 × cos 86
X = 57× 0.06976
X = 3.97 = 4m
The keys would fall from the tower's base at a distance of about 4 meters.
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Which of the following points is in the solution set of y < x2 - 2x - 8? O 1-2. -1) O 10.-2) 0 (4.0)
Given the functon
[tex]yExplanation
To find the points that lie in the solution set we will lot the graph of the function and indicate the ordered pirs.
From the above, we can see that the right option is
Answer: Option 1
help meeeeeeeeee pleaseee !!!!!
The values of the functions are;
a. (f + g)(x) = x( 2 + 3x)
b. (f - g)(x) = 2x - 3x²
c. (f. g) (x) = 6x²
d. (f/g)(x) = 2/ 3x
What is a function?A function can be defined as an expression, rule, law or theorem that explains the relationship between two variables in a given expression
These variables are called;
The independent variablesThe dependent variablesFrom the information given, we have;
f(x) = 2xg(x) = 3x²To determine the composite functions, we have;
a. (f + g)(x)
Add the functions
(f + g)(x) = 2x + 3x²
Factorize the functions
(f + g)(x) = x( 2 + 3x)
b. (f - g) (x)
Subtract the functions
(f - g)(x) = 2x - 3x²
c. (f. g) (x)
Substitute the values of x as g(x) in f(x)
(f. g) (x) = 2(3x²)
(f. g) (x) = 6x²
d. (f/g)(x) = 2x/ 3x²
(f/g)(x) = 2/ 3x
Hence, the functions are determined by substituting the values of the dependent variables.
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if q(x)= int 0 ^ x^ 3 sqrt 4+z^ 6 dz then
Solution:
Given that:
For the bird, determine the following: The maximum height The axis of symmetry The total horizontal distance travelled A quadratic equation written in vertex form
Explanation:
The table of values is given below as
Using a graphing tool, we will have the parabola represented below as
On the planet Alaber, there are 15 dubbles to every 13 rews. If farmer Mimstoon has 100 rews on his frent farm, how many dubbles are on the farm?
You have that on planet Alaber, there are 15 dubbles to every 13 rews. This proportion can be wrtten as 15:13, or 15/13.
In order to calculate how many dubbles are on the farm, while there are 100 rews. You use the previous ratio and proceed as follow:
15/13 = x/100 where x is the unknown number of dubbles
This is because the ratio between dubbles and rews must be the same.
You solve the previous equation as follow:
15/13=x/100 multiply both sides by 100 to cancel the denomitaro 100 right side
15/13(100) = x/100(100)
1500/13 = x
In order to write the previous result as a mixed number you divide numerator and denominator:
1500 | 13
143 115
70
65
5
Then, x = 1500/13 is also equal to:
x = 115 13/5
This means there are approximately 115 dubbles for 100 rews
For the quadratic function, identify any horizontal or vertical translations. Enter "0" and "none" if there is none.f(x) = (x + 5)² - 4Horizontal:__ units to the (Select an answer (right, left, none)Vertical:__ units to the (Select an answer ( up, down, none)
Given:
[tex]f(x)=(x+5)^2-4[/tex]The parent function of the given function (x²)
We will find the horizontal or vertical translations to get the given function.
the general form of the translation will be as follows:
[tex]f(x\pm a)\pm b[/tex]Where (a) is the horizontal translation and (b) is the vertical translation
Comparing the given equation to the formula:
[tex]a=5,b=-4[/tex]So, the answer will be:
Horizontal: 5 units to the left
Vertical: 4 units down
Express $20.35 as an equation of working h hours, when I equals income
Let
I ------> income in dollars
h -----> number of hours
$20.35 is the hourly pay
so
the linear equation that represent this situation is
I=20.35*hHow long will it take money to double if it is invested at the following rates?(A) 7.8% compounded weekly(B) 13% compounded weekly(A) years(Round to two decimal places as needed.)
Answer:
Explanation:
A) We'll use the below compound interest formula to solve the given problem;
[tex]A=P(1+r)^t[/tex]where P = principal (starting) amount
A = future amount = 2P
t = number of years
r = interest rate in decimal = 7.8% = 7.8/100 = 0.078
Since the interest is compounded weekly, then r = 0.078/52 = 0.0015
Let's go ahead and substitute the above values into the formula and solve for t;
[tex]\begin{gathered} 2P=P(1+0.0015)^t \\ \frac{2P}{P}=(1.0015)^t \\ 2=(1.0015)^t \end{gathered}[/tex]Let's now take the natural log of both sides;
[tex]\begin{gathered} \ln 2=\ln (1.0015)^t \\ \ln 2=t\cdot\ln (1.0015) \\ t=\frac{\ln 2}{\ln (1.0015)} \\ t=462.44\text{ w}eeks \\ t\approx\frac{462.55}{52}=8.89\text{ years} \end{gathered}[/tex]We can see that it will take 8.89 years for
B) when r = 13% = 13/100 = 0.13
Since the interest is compounded weekly, then r = 0.13/52 = 0.0025
Let's go ahead and substitute the values into the formula and solve for t;
[tex]\begin{gathered} 2P=P(1+0.0025)^t \\ \frac{2P}{P}=(1.0025)^t \\ 2=(1.0025)^t \end{gathered}[/tex]Let's now take the natural log of both sides;
[tex]\begin{gathered} \ln 2=\ln (1.0025)^t \\ \ln 2=t\cdot\ln (1.0025) \\ t=\frac{\ln 2}{\ln (1.0025)} \\ t=277.60\text{ w}eeks \\ t\approx\frac{2.77.60}{52}=5.34\text{ years} \end{gathered}[/tex]