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Instructions: Show your steps clearly. Write your justification as to why you wi

ID: 2912822 • Letter: I

Question

Instructions: Show your steps clearly. Write your justification as to why you will be using the formulas in each step. 1. Dan Hook deposits $400 a month to a retirement account that has interest rate of 3.1%, compounded monthly. After making 60 deposits, Dan changes his job and stops making payments for 3 years. After 3 years, he starts making deposits again, but now he deposits $525 monthly. What will the total value of the retirement accounts be a. After Dan makes his $400 monthly deposit for five years? b. Eight years after his first deposit of $400? c. After Dan makes his $525 monthly deposits for 5 years?

Explanation / Answer

The formula for annual compound interest, including principal sum, is:

A = PMT * (((1 + r/n)^nt - 1) / (r/n)) * (1+r/n)

Where:

A = The future value of the Deposit, including interest

P = the principal Deposit amount

PMT = the monthly payment

r = the annual interest rate

n = the number of times that interest is compounded per year (i.e Monthly)

t = the number of years the money is invested or borrowed for

A = [ $400 * (((1 + 0.031/12)60 - 1) / (0.031/12)) ]

A = $25,990.78

After stop making payment

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

A = $25990.78 * ( 1+.031/12) (12*3)

A = $28520.47

After 3 years, A :

A = [ Compound interest for principal ] + [ Future value of a series ]

A =  [ P(1+r/n)^(nt) ] + [ PMT * (((1 + r/n)^nt - 1) / (r/n)) ]

A = $28520.47 *( 1+.031/12) (12*5) + [ $525 * (((1 + 0.031/12)60 - 1) / (0.031/12)) ]

A = $ 67,408.40

The value of the retirement account after Dan makes his $525 monthly deposits for 5 years would be $ 67,408.40.