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Brittany will be working full time this summer to save for her goal of having 10,000 by the time she is 21. Brittany has an account of 3.5% interest, compounded monthly. She'll turn 17 at the end of the summer. About how much will Brittany have to deposit so that. Her money can grow into 10,00 by the time she's 21?

User Michah
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1 Answer

5 votes

Answer:

$ 8,695.35

Explanation:

This is a compound interest question

Amount after t years = A = P(1 + r/n)^nt

Where P = Initial Amount saved

r = interest rate

t = time in years

n = compounding frequency

A = 10,000

r = 3.5 %

t = 21 - 17 = 4 years

n = Compounded monthly = 12

Step 1

Converting R percent to r a decimal

r = R/100 = 3.5%/100 = 0.035 per year.

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

Solving our equation:

P = 10000 / ( 1 + (0.035/12)^12 ×4 =

P = $8,695.35

The principal investment required to get a total amount, principal plus interest, of $10,000.00 from interest compounded monthly at a rate of 3.5% per year for 4 years is $8,695.35.

User Sonichy
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