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Jasica Parker would like to have $48,000 to buy a new car in 7 years. To accumulate $48,000 in 7 years, how much should she invest monthly in a sinking fund with

3% interest compounded monthly?
The monthly invested payment is $
(Do not round until the final answer. Then round up to the nearest cent.)

1 Answer

6 votes

Answer:

$38,918.25

Explanation:

The equation you want to use for this is
A=P(1+(r)/(n))^(nt):

  • A = final Amount
  • P = Principal (invested) amount
  • r = interest Rate (as a decimal)
  • n = the Number of times compounded each year
  • t = the Time in years

You need to find P, so set up your equation:


48000=P(1+(.03)/(12))^(12*7)

Use the Order of Operations to simplify
(1+(.03)/(12))^(12*7):

(1+(.03)/(12))^(12*7)=(1+.0025)^(84)=1.0025^(84)

Now solve for P:

48000=P(1.0025^(84))

P=(48000)/(1.0025^(84)) ≈ 38918.24151

You'll want to round UP instead of off, because you're trying to find out how much to invest in order to have $48,000 and not still need a penny or two.

User Takayoshi
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