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Heather received $100 for her 13th birthday if she saves it in a bank with 3% interest compounded quarterly how much money will she have in the bank by her 16th birthday​

User Henry Lynx
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1 Answer

4 votes

Answer:

109.38

Explanation:

Recall the formula for compound interest is as follows:

A = P·(1 + r/n)nt , where

P = principal amount (initial amount deposited)

r = annual rate of interest (in decimal form)

t = # of years amount is deposited for

n = # of times interest is compounded per year

A = amount accumulated after t years, including interest

The problem asks how much money Heather will have in the bank by her 16th birthday when she deposited $100 on her 13th birthday in a bank with 3% interest compounded quarterly. From this, we have the following information:

P = $100

r = 0.03 ==> 3%/100% = 0.03

t = 3 years ==> 16 - 13 = 3

n = 4 ==> since there are 12 months per year and 12/4 = 3 months,

then interest is compounded every 3 months which is a total of 4 times per year

Therefore,

A = P(1 + r/n)nt

= 100(1 + 0.03/4)4·3

= 100(1 + 0.0075)12

= 100(1.0075)12

= 109.38069

≈ 109.38

Thus, Heather will have $109.38 in the bank by her 16th birthda

User Tony J Huang
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