Given 7 women and 10 men;
a) the top 3 are all men:
[tex]\begin{gathered} ways\text{ to choose 3 men out of 10 men is:} \\ 10C_3=\frac{10!}{(10-3)!3!} \\ \Rightarrow\frac{10!}{7!3!}=\frac{10\times9\times8\times7!}{7!\times3\times2\times1} \\ \Rightarrow\frac{10\times9\times8}{3\times2\times1}=120 \\ \text{ways to choose 3 men from 17 people(10men +7women) is:} \\ 17C_3=\frac{17!}{(17-3)!3!} \\ \Rightarrow\frac{17!}{14!\times3!}=\frac{17\times16\times15\times14!}{14!\times3\times2\times1} \\ \Rightarrow\frac{17\times16\times15}{3\times2\times1}=680 \end{gathered}[/tex]Therefore, the probability that the top 3 are all men is:
[tex]P_{all\text{ men}}=\frac{120}{680}=0.1765[/tex]b) the top 3 are all women:
[tex]\begin{gathered} \text{ways to choose 3 women from 7 women is:} \\ 7C_3=35 \\ \text{ways to choose 3 women from 17 people is:} \\ 17C_3=680 \end{gathered}[/tex]Therefore, the probability that the top 3 are all women is:
[tex]P_{\text{all women}}=\frac{35}{680}=0.0515[/tex]c) 2 men and 1 woman;
[tex]\begin{gathered} ways\text{ to choose 2 men out of 10 men is:} \\ 10C_2=45 \\ \text{ways to choose 1 woman from 7 women is:} \\ 7C_1=7 \\ \text{Thus, ways to choose 2 men and 1 woman }=45\times7=315 \end{gathered}[/tex]Therefore, the probability that the top 3 finishers are 2 men and 1 woman is:
[tex]P=\frac{315}{680}=0.4632[/tex]d) 1 man and 2 women;
[tex]\begin{gathered} \text{ways to choose 1 man from 10 men is;} \\ 10C_1=10 \\ \text{ways to choose 2 women from 7 women is:} \\ 7C_2=21 \\ \text{Thus, ways to choose 1 man and 2 women is 10}\times21=210 \end{gathered}[/tex]Therefore, the probability that the top 3 finishers are 1 man and 2 women is:
[tex]P=\frac{210}{680}=0.3088[/tex]yesenia knits 21 centimeters of a scarf every week. what Is yesenia's unit rate (cm per day)for her knitting?After 18 days of knitting, how many centimeters long will the scarf be?write an equation and solve.
Answer:
3cm per day
54cm long
Explanation
Let x be yesenia's unit rate
If yesenia knits 21 centimeters of a scarf every week, then;
21 cm = 1 week (7 days)
To determine the amount for her knitting in a day, we can write;
x = 1 day
Divide both expressions
21/x = 7/1
Cross multiply
7 * x = 21
7x = 21
x = 21/7
x = 3
hence yesenia's unit rate is 3cm per day
- Recall that;
21 cm = 1 week (7 days)
Let y be the length of the scaf sfter 18 days, To get the length of the scarf, we can write;
y = 18days
Divide both resulting expressions;
21/y = 7/18
7y = 21 * 18
y = 3 * 18
y = 54cm
Hence the scarf will be 54cm longy
help meeeeeeeeeeeeeeeeeeeeeee
Suppose that a household's monthly water bill (in dollars) is a linear function of the amount of water the household uses (in hundreds of cubic feet, HCF). When graphed, the function gives a line with a slope of 1.45. See the figure below.
If the monthly cost for 22 HCF is $45.78, what is the monthly cost for 19 HCF?
Using a linear function, it is found that the monthly cost for 19 HCF is of $41.43.
What is a linear function?A linear function, in slope-intercept format, is modeled according to the rule presented below:
y = mx + b
In which the parameters of the function are described as follows:
The coefficient m is the slope of the function, representing the rate of change of the function, that is, the change in y divided by the change in x.The coefficient b is the y-intercept of the function, which is the value of y when the function crosses the y-axis(x = 0).As stated in the problem, the slope is of 1.45, hence:
y = 1.45x + b.
The monthly cost for 22 HCF is $45.78, hence when x = 22, y = 45.78, meaning that the intercept b can be found as follows:
45.78 = 1.45(22) + b
b = 45.78 - 1.45 x 22
b = 13.88.
Then the function is:
y = 1.45x + 13.88.
And the cost for 19 HCF is given by:
y = 1.45(19) + 13.88 = $41.43.
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Lines PQ and Rs are parallel. Find y. P(2, -5); Q(5, 6); R(3, -1); S(6, y)y = ?
To answer this question it is necessary to find the equation of the given lines
Find the equation for PQ. To do it, find the slope of the equation:
[tex]m=\frac{6-(-5)}{5-2}=\frac{11}{3}[/tex]Now, use the point slope formula to find the equation of the line:
[tex]\begin{gathered} y-6=\frac{11}{3}(x-5) \\ y=\frac{11}{3}x-\frac{55}{3}+6 \\ y=\frac{11}{3}x-\frac{37}{3} \end{gathered}[/tex]Parallel lines have the same slope, it means PQ and RS have the same slope, then RS has a slope of 11/3
Use the point slope formula to find the equation of the line RS:
[tex]\begin{gathered} y-(-1)=\frac{11}{3}(x-3) \\ y+1=\frac{11}{3}x-11 \\ y=\frac{11}{3}x-12 \end{gathered}[/tex]Now, use this equation to find y when x is 6 (which corresponds to point S):
[tex]\begin{gathered} y=\frac{11}{3}x-12 \\ y=\frac{11}{3}(6)-12 \\ y=22-12 \\ y=10 \end{gathered}[/tex]y has a value of 10.
A theater group made appearances in two cities. The hotel charge before tax in the second city was $500 higher than in the first. The tax in the first city was5%, and the tax in the second city was 6%. The total hotel tax paid for the two cities was $552.50. How much was the hotel charge in each city before tax?Note that the ALEKS graphing calculator can be used to make computations easier.
SOLUTION
Let us represent the hotel charge with different variables x and y:
Let the hotel charge before tax in the first city be x
Let the hotel charge before tax in the second city be y
Now, let us represent the word problem in equation form:
First, we were told that the charge before tax in the second city is $500 more than the charge before tax in the first city, this can be represented thus:
[tex]y=x+500\ldots\text{.eqn 1}[/tex]Going forward in the question, we were told the tax for the first city (x) is 5%(0.05), and the tax for the second city is 6%(0.06). The total tax from both cities is $552.5, this expression can be written mathematically as:
[tex]0.05x+0.06y=552.5\ldots\ldots\text{eqn 2}[/tex]Now, by solving equation 1 and equation 2 simultaneously, we will obtain the hotel charge in each city before tax. (that is the value of x and y).
[tex]\begin{gathered} y=x+500 \\ 0.05x+0.06y=552.5 \\ \end{gathered}[/tex]Using, the substitution method of solving simultaneous equation, we will solve further:
[tex]\begin{gathered} \text{substitute equation 1 into equation 2} \\ 0.05x+0.06(x+500)=552.5 \\ 0.05x+0.06x+30=552.5 \\ 0.11x+30=552.5 \end{gathered}[/tex][tex]\begin{gathered} 0.11x=552.5-30 \\ 0.11x=522.5 \\ x=\frac{522.5}{0.11} \\ x=4750 \end{gathered}[/tex]The hotel charge before tax in the first city is $4750.
Now, substitute the value of x into equation 1 to get the value of y (hotel charge before tax in the second city)
[tex]\begin{gathered} y=x+500 \\ x=4750 \\ y=4750+500 \\ y=5250 \end{gathered}[/tex]The hotel charge before tax in the second city is $5250.
Finding the time given an exponential function with base e that models a real-world situation
We are solving for the value of t if C(t) = 19. We can rewrite the equation into
[tex]19=5+17e^{-0.038t}[/tex]Solving for t, we have
[tex]\begin{gathered} 17e^{-0.038t}=19-5 \\ 17e^{-0.038t}=14 \\ e^{-0.038t}=\frac{14}{17} \\ -0.038t=\ln \frac{14}{17} \\ -0.038t=-0.1941 \\ t=\frac{-0.1941}{-0.038} \\ t\approx5.1 \end{gathered}[/tex]The bottled water will achieve a temperature of 19 degrees C after 5.1 minutes.
Answer: 5.1 min
Zach can buy a dozen pencils for $1.89, 24 pencils for $3.60, or 36 pencils for $5.49. What is the best buy?
To know which one is the best option we have to divide the cost in the number of pencils so:
[tex]\frac{1.89}{12}=0.16[/tex]the second option is:
[tex]\frac{3.60}{24}=0.15[/tex]the thert option is:
[tex]\frac{5.49}{36}=1.16[/tex]So the best option is the second option
4. (A.20) Natasha and her friends go out for ice cream. They decide to create their own ice cream, which costs $1.60 plus 8 cents per topping. If x represents the number of toppings on the ice cream, then which'equation describes y, the total cost for the ice cream?A. y = 0.08 + 1.60)x B. y = .08 + 1.60x C. y = 1.60 +.08x D. y = 8x + 1.60
Answer:
C. y = 1.60 +.08x
Explanation:
The cost of the ice cream will be equal to the fixed cost of $1.60 plus the cost that depends on the number of toppings. So, if Natasha chooses x number of topping, the total cost of the toppings will be 8 cents times x or $0.08x
So, the total cost for the ice cream is represented by the equation:
y = 1.60 +.08x
Below is the graph of a parabola with its vertex and another point on the parabola labeled.Write an equation of the parabola.(-2,4).(1, -2)
The vertex form of a parabola is given by:
[tex]x=a(y-k)^2+h[/tex]Where the vertex is:
[tex]\begin{gathered} V(h,k)=(-2,4) \\ so\colon \\ x=a(y-4)^2-2 \\ x=a(y-4)^2-2 \end{gathered}[/tex]for (1,-2):
[tex]\begin{gathered} 1=a(-2-4)^2-2 \\ 1=a(-6)^2-2 \\ 1=36a-2 \\ solve_{\text{ }}for_{\text{ }}a\colon \\ 36a=1+2 \\ 36a=3 \\ a=\frac{3}{36} \\ a=\frac{1}{12} \\ \end{gathered}[/tex]therefore:
[tex]x=\frac{1}{12}(y-4)^2-2[/tex]turn 5 7/10 into a decimal and a percent
It is a mixed number:
[tex]5\frac{7}{10}[/tex]THe whole part, 5, is going to stay 5.
Now, let's work with the fractional part.
7/10 into a decimal would require for division.
7 divided by 10 is 0.7
Thus,
IN Decimal, it will be "5.7"
To find percentage from decimal, we multiply by 100 and tag along a % sign.
So,
[tex]5.7\cdot100=570[/tex]The number, in percentage, is 570%
HELP PLEASE!!!!!!!!!!! ILL MARK BRAINLIEST
the rational number :
-1 ³/₄ is located as point 1
14/8 is located as point 5
1.125 is located as point 6
-0.875 is located as point 4
What is number line ?
Number line is virtual representation of numbers along with coordinates axis with number equally spaced with equal number of interval.
Here,
the rational number -1 ³/₄ is located as point 1, as -1 ³/₄ is greater then -1 and less then -2 on number line and is 3/4 of the gap between -1 and -2.
the rational number 14/8 is located as point 5, as 14/8 is greater then 0 and less then 1 on number line and is 3/4 of the gap between 0 and 1.
the rational number 1.125 is located as point 6, as 1.125 is greater then 1 and less then 2 on number line and is 1/8th of the gap between 1 and 2.
the rational number -0.875 is located as point 4, as -0.875 is greater then 0 and less then -1 on number line and is 1/8 th of the gap between -1 and 0.
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Let f(t) = 3 + 2, g(x) = -x^2?, andhe) = (x - 2)/5. Find the indicated value:24. h (g(5))
The Solution to Question 24:
Given the function below:
[tex]\begin{gathered} g(x)=-x^2 \\ h(x)=\frac{x-2}{5} \end{gathered}[/tex]We are asked to find the value of h(g(5)).
Step 1:
We shall find g(5) by substituting 5 for x in g(x).
[tex]g(5)=-5^2=-25[/tex]So that:
[tex]h(g(5))=h(-25)[/tex]Similarly, we shall find h(-25) by substituting -25 for x in h(x).
[tex]h(-25)=\frac{-25-2}{5}=\frac{-27}{5}[/tex]Therefore, the correct answer is
[tex]\frac{-27}{5}[/tex]how do I know where which choices below go into the correct blanks for number 1-4?
For 1, we have the following triangle:
Using the cosine function to get the hypotenuse we get:
[tex]\begin{gathered} \cos (45)=\frac{7}{h} \\ \Rightarrow h=\frac{7}{\cos(45)}=\frac{7}{\frac{1}{\sqrt[]{2}}}=7\cdot\sqrt[]{2} \\ h=7\cdot\sqrt[]{2} \end{gathered}[/tex]Now that we have the hypotenuse, we can find the remaining side using the pythagorean theorem:
[tex]\begin{gathered} h^2=7^2+x^2 \\ \Rightarrow x^2=h^2-7^2=(7\cdot\sqrt[]{2})^2-7^2=49\cdot2-49=49 \\ \Rightarrow x^2=49 \\ x=7 \end{gathered}[/tex]Therefore, the value of the remaining side is 7.
How to fill out an income summary
Answer: Pick a Reporting Period. ...
Generate a Trial Balance Report. ...
Calculate Your Revenue. ...
Determine the Cost of Goods Sold. ...
Calculate the Gross Margin. ...
Include Operating Expenses. ...
Calculate Your Income. ...
Include Income Taxes.
Theo sales person makes $350 each week plus an additional $28 per sale. Theo wants his paycheck to be at least $550 each week. Solve the inequality and choose the best answer to the scenario.
Which angles are adjacent to <2? Select all that apply.
In the equation y = 2x, y represents the perimeter of a square.What does x represent?Ahalf the length of each sideBthe length of each sideСtwice the length of each sideDtwice the number of sides
Given:
An equation that represents the perimeter of a square:
[tex]y=2x[/tex]To find:
What x represents.
Solution:
It is known that the perimeter of the square is equal to four times the side of the square.
Let the side of the square be s. So,
[tex]\begin{gathered} y=P \\ 2x=4s \\ x=\frac{4s}{2} \\ x=2s \end{gathered}[/tex]Therefore, x represents twice the length of each side.
I dont know how to complete this please help.
A' ∩ C U B in roster form is {3, 7, 8, 9}
What is A' ∩ C U B?To write a set in a roster form, the elements in the set are written in a row within curly brackets.
The following are set symbols and their meaning:
• U = union = it means all the elements in two or more sets.
• ∩ = intersection = it means elements that are common to two or more sets.
• ' = complement = it means elements that are not in the set but in the universal set.
A' = {3, 6, 7, 8, 9}
C U B = {2, 3, 4, 5, 7, 8, 9}
A' ∩ C U B = {3, 7, 8, 9}
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Given the exponential decay function below:Determine the intervals of increase and decrease.
Given the equation of exponential decay function:
[tex]y=(\frac{1}{3})^x-3[/tex]The given function always decreases overall the domain
so, the answer will be the intervals of decrease is:
[tex](-\infty,\infty)[/tex]Please Help!!!!! NOT FOR QUIZ!!!!!!!!
The graph of the line y [tex]=[/tex] -3x + 4 is a line that shows the set of all solutions to the equation , the correct option is (c) .
In the question ,
it is given that
the equation of the line is y [tex]=[/tex] -3x + 4 ,
we have to plot the line in the coordinate plane .
we plot the line ,w e need at least two points .
for the first point ,
for x = 0 , we have
y = -3(0) + 4
y= 0 + 4
y = 4
the first point is (0,4)
for the second point
for y = 0 , we have
0 = -3x + 4
-3x = -4
x = 4/3
the second point is (4/3 , 0)
so , from the graph plotted below , we can see that the line y [tex]=[/tex] -3x+4 shows the set of all solutions to the equations .
Therefore , The graph of the line y [tex]=[/tex] -3x + 4 is a line that shows the set of all solutions to the equation .
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a company loses $5,400 as the result of manufacturing defect. each of the 8 owners have agreed to pay an equal amount, x, to pay for the loss. How much each owner paid?
Explanation:
If 'x' is the amount each owner will pay, there are 8 owners and the total amount to pay is $5,400 the equation to solve is:
[tex]8x=5,400[/tex]Solving for x:
[tex]x=\frac{5,400}{8}=675[/tex]Answer:
Each owner has to pay $675
Complete the remander of the
table for the given function rule:
y = 3x-8
X= -4,-2,0,2,4
Y=-20,?,?,?
Step-by-step explanation:
what is the problem ?
all you need to do is put every different value of x into the spot of x and calculate the result.
x = -4
y = 3×-4 - 8 = -12 - 8 = -20
x = -2
y = 3×-2 - 8 = -6 - 8 = -14
x = 0
y = 3×0 - 8 = 0 - 8 = -8
x = 2
y = 3×2 - 8 = 6 - 8 = -2
x = 4
y = 3×4 - 8 = 12 - 8 = 4
Aaquib can buy 25 liters of regular gasoline for $58.98 or 25 liters of permimum gasoline for 69.73. How much greater is the cost for 1 liter of premimum gasolinz? Round your quotient to nearest hundredth. show your work :)
The cost for 1 liter of premium gasoline is $0.43 greater than the regular gasoline.
What is Cost?This is referred to as the total amount of money and resources which are used by companies in other to produce a good or service.
In this scenario, we were given 25 liters of regular gasoline for $58.98 or 25 liters of premium gasoline for $69.73.
Cost per litre of premium gasoline is = $69.73 / 25 = $2.79.
Cost per litre of regular gasoline is = $58.98/ 25 = $2.36.
The difference is however $2.79 - $2.36 = $0.43.
Therefore the cost for 1 liter of premimum gasoline is $0.43 greater than the regular gasoline.
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Create an equation that models the table below. Use the variables in the table for your equation. Write your equation with 'S' isolated.
The table show piszzas (P) on the left column and the slices of Pepperonin (S) on the right column.
To determine the equation models first check the ratio S/P to determine whether they are proportinal or not.
[tex]\begin{gathered} \frac{36}{3}=12 \\ \frac{96}{8}=12 \\ \frac{228}{19}=12 \end{gathered}[/tex]Now as the ratios are constant it mean the variation is linear and the relationship is proportional.
Thus the model equation can be determine as,
[tex]\begin{gathered} \frac{S}{P}=12 \\ S=12P \end{gathered}[/tex]Thus, the above equation gives the required model equation.
The flow of water from a faucet can fill a 4-gallon container in 28 seconds Give the ratio of gallons to seconds as a rate in gallons per second and as a reduced fraction. The faucet fills the container at rate of——gallon per second
The flow of water can fill a 4-gallon container in 28 seconds.
Given:
Number of gallons = 4
Time = 28 seconds
Hence, the ratio of gallons to seconds will be 4 : 28
[tex]\begin{gathered} As\text{ a rate in gallons per second = }\frac{\text{number of gallons}}{time\text{ taken}} \\ As\text{ a rate in gallons per second = }\frac{4}{28}=\frac{1}{7} \\ As\text{ a reduced fraction, the rate in gallons per second is }\frac{1}{7}\text{gallons per second} \end{gathered}[/tex]Therefore, the faucet fills the container at the rate of 1/7 gallon per second
Which situation represents a proportional relationship?
O Renting a movie for $2 per day
O Renting a movie for $2 per day with a coupon for $0.50 off for the first day
O Renting a movie for $2 per day along with paying a $5 membership fee
O Renting a movie for $2 for the first day and $1 for each day after the first day
As they are in the right ratio, option D, "Renting a movie for $2 for the first day and $1 for each day after the first day," demonstrates a proportionate relationship.
Proportional Relationship
When two variables' ratios are equivalent, proportional relationships between them emerge. The fact that one variable is consistently equal to the constant value of the other in a proportional connection is another way to think of them. This constant is known as the "constant of proportionality."
Ratio
In mathematics, a ratio shows how frequently one number appears in another. For instance, the ratio of apples to mangos in a bowl of fruit would be nine to six if there were nine apples and six mangos. Apples make up 9:15 of the entire fruit, whereas Mangos make up 6:9 of the total fruit.
Option D, "Renting a movie for $2 for the first day and $1 for each day after the first day," illustrates a proportional relationship because the ratio is correct
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Please help me I need this done fast I will give brainliest to whoever answers first
Consider that a standard quadratic equation is given by,
[tex]y=ax^2+bx+c[/tex]The curve passes through the point (-5,0),
[tex]\begin{gathered} 0=a(-5)^2+(-5)b+c \\ 0=25a-5b+c \\ c=-25a+5b\ldots\ldots\ldots(1) \end{gathered}[/tex]The curve passes through the point (3,0),
[tex]\begin{gathered} 0=a(3)^2+(3)b+c \\ 0=9a+3b+c \end{gathered}[/tex]Substitute value from equation (1),
[tex]\begin{gathered} 0=9a+3b+(-25a+5b) \\ 0=-16a+8b \\ b=2a\ldots\ldots\ldots(2) \end{gathered}[/tex]The curve passes through the point (4,9),
[tex]\begin{gathered} 9=a(4)^2+(4)b+c \\ 9=16a+4b+c \end{gathered}[/tex]Substitute tha values from (1) and (2),
[tex]\begin{gathered} 9=16a+4(2a)+(-25a+5(2a)) \\ 9=16a+8a-25a+10a \\ 9=9a \\ a=1 \end{gathered}[/tex]Substitute in equation (2),
[tex]\begin{gathered} b=2(1) \\ b=2 \end{gathered}[/tex]Substitute the values in equation (1),
[tex]\begin{gathered} c=-25(1)+5(2) \\ c=-25+10 \\ c=-15 \end{gathered}[/tex]Substitute the values of a, b, and c, in the standard equation,
[tex]\begin{gathered} y=(1)x^2+(2)x+(-15) \\ y=x^2+2x-15 \end{gathered}[/tex]This is the equation of the given parabola.
Therefore, option B is the correct choice.
simplify 12 times y to the 6th power times z to the 4th power divided by 6 times y times z to the 6th power
The simplified expression of the given expression is 2y^5 z^{-2}
What is expression?
A mathematical expression is a phrase that includes at least two numbers or variables, at least one arithmetic operation, and the expression itself. Any one of the following mathematical operations can be used.
Given expression, [tex]\frac{12y^6 z^4}{6 yz^6}[/tex]
Simplifying and we get
[tex]\frac{12y^6 z^4}{6 yz^6}\\=2y^{6-1} z^{4-6}\\=2y^5 z^{-2}[/tex]
Therefore, the simplified expression of the given expression is 2y^5 z^{-2}
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Sort the sequences according to whether they are arithmetic, geometric, or neither. (98.3, 94.1, 89.9, 85.7,) (1, 0, -1, 0) (1.75, 3.5, 7, 14) (-12, -10.8, -9.6, -8.4) (-1, 1, -1, 1)
hello
to know what type of sequence they are, we need to test either for common difference of common ratio
first sequence
(98.3, 94.1, 89.9)
first term = 98.3
in this case there's a common difference here
we can find that by subtracting the second term from the first term or the third term from the second term
[tex]\text{common difference (d) = 94.1-98.3=-4.2}[/tex]first sequence is an arithmetic progression
second sequence
(1, 0, -1, 0)
first term = 1
common difference or common ratio does not exist here
third sequence
(1.75, 3.5, 7, 14)
first term = 1.75
in this case, there's no common difference but rather common ratio
common ratio (r) can be found by dividing the second term by the first term or the third term by the second term
[tex]\begin{gathered} \text{common ratio(r) = }\frac{3.5}{1.75}=2 \\ \frac{14}{7}=2 \end{gathered}[/tex]the common ratio here is 2 and this is a geometric progression
fourth sequence
(-12, -10.8, -9.8, -8.4)
first term = -12
in this sequence, there's no common difference or common ratio
fifth sequence
(-1, 1, -1, 1)
the fifth sequence is neither a geometric or artimethic progression because there no common difference or ratio
How long will it take for an investment of 2900 dollars to grow to 6800 dollars, if the nominal rate of interest is 4.2 percent compounded quarterly? FV = PV(1 + r/n)^ntAnswer = ____years. (Be sure to give 4 decimal places of accuracy.)
ANSWER :
The answer is 20.3971 years
EXPLANATION :
The compounding interest formula is :
[tex]FV=PV(1+\frac{r}{n})^{nt}[/tex]where :
FV = future value ($6800)
PV = present value ($2900)
r = rate of interest (4.2% or 0.042)
n = number of compounding in a year (4 : compounded quarterly)
t = time in years
Using the formula above :
[tex]6800=2900(1+\frac{0.042}{4})^{4t}[/tex]Solve for t :
[tex]\begin{gathered} \frac{6800}{2900}=(1.0105)^{4t} \\ \text{ take ln of both sides :} \\ \ln(\frac{6800}{2900})=\ln(1.0105)^{4t} \\ \operatorname{\ln}(\frac{6800}{2900})=4t\operatorname{\ln}(1.0105) \\ 4t=\frac{\ln(\frac{6800}{2900})}{\ln(1.0105)} \\ t=\frac{\ln(\frac{6800}{2900})}{4\ln(1.0105)} \\ t=20.3971 \end{gathered}[/tex]