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13. Use the appropriate percent growth to determine how much money Lyra will have in each ofthe following situations:(a) How much money will Lyra have after 10 years if she invests $5,000 at 4% interest com-pounded annually?(b) Suppose that Lyra is saving for retirement, and has saved up $20,000. If her retirementaccount earns 3% interest each year, how much will she save in 25 years?(c) How much money will Lyra have after 20 years if she $5,000 at 3.5% interest compoundedannually?(d) How much money will Lyra have after 10 years if she invests $5,000 at 1.5% interestcompounded quarterly?(e) How much money will Lyra have after 10 years if she invests $5,000 at 0.8% interestcompounded continuously?(f) Compare your answers to (a) and (c). Which one made more money, and does the resultsurprise you?

13. Use the appropriate percent growth to determine how much money Lyra will have-example-1

1 Answer

3 votes

Answer:

a) 7401.22

b) 35000

c) 9948.94

d) 5807.54

e) 5416.44

f)(c) made more money. I'm not surprised because c has more years

Step-by-step explanation:

The formula for calculating compound interest is expressed as

A = P(1 + r/n)^nt

where

A is the total amount after t years

P is the principal or amount invested

r is the interest rate

n is he number of compounding periods in a year

t is the number of years

a) From the information given,

P = 5000

r = 4% = 4/100 = 0.04

t = 10

n = 1 because it was compounded once per year.

By substituting these values into the formula, we have

A = 5000(1 + 0.04/1)^1 * 10

A = 5000(1.04)^10

A = 7401.22

b) From the information given,

P = 20000

r = 3% = 3/100 = 0.03

t = 25

This is simple interest. The formula for calculating simple interest is expressed as

I = Prt

By substituting the values,

I = 20000 x 0.03 x 25 = 15000

Total amount after 25 years = P + I = 20000 + 15000

Total amount after 25 years = 35000

c) From the information given,

P = 5000

r = 3.5% = 3.5/100 = 0.035

t = 20

n = 1 because it was compounded once per year.

By substituting these values into the formula, we have

A = 5000(1 + 0.035/1)^1 * 20

A = 5000(1.035)^20

A = 9948.94

d) From the information given,

P = 5000

r = 1.5% = 1.5/100 = 0.015

t = 10

n = 4 because it was compounded quarterly.

By substituting these values into the formula, we have

A = 5000(1 + 0.015/4)^4 * 10

A = 5000(1.00375)^40

A = 5807.54

e) The formula for calculating continuously compounded interest is expressed as

A = Pe^rt

From the information given,

P = 5000

r = 0.8% = 0.8/100 = 0.008

t = 10

By substituting these values into the formula, we have

A = 5000e^(0.008 * 10)

A = 5000e^(0.08)

A = 5416.44

f) By comparing (a) and (c), (c) made more money. I'm not surprised because c has more years

User Andrew Sun
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