Answer:
16 1/4 years
Explanation:
Assuming interest is compounded annually, the account balance (A) after t years will be ...
A = P(1 +r)^t
3200 = 1700·1.0397^t
log(3200) = log(1700) +t·log(1.0397)
t = (log(3200) -log(1700))/log(1.0397) ≈ 16.247
The account will reach a balance of $3200 after about 16 1/4 years.
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