Answer:
3.00%
Explanation:
You want the interest rate that will make an $8000 deposit achieve a value of $9571.31 in 6 years when interest is compounded quarterly.
Compound Interest
The compound interest formula can be solved for the interest rate when other values are known:
A = P(1 +r/n)^(nt) . . . . . . . interest at rate r compounded n times per year
9571.31 = 8000(1 +r/4)^(4·6) . . . . fill in known values
(9571.31/8000)^(1/24) = 1 +r/4
1 +r/4 ≈ 1.0075000
r ≈ 0.0075000 × 4 ≈ 3.00%
The interest rate is 3.00%.
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Additional comment
A financial calculator, app, or spreadsheet can find this for you.