Answer: (a) 3270 (b) 6270
Explanation:
Formula for compound interest: P (1 + r/100 ) ^n,
where P = principal, r = interest rate, n = number of years
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In question (a),
P = $3000
r = 9%
n = 1
3000 ( 1 + 9/100) ^1 = $3270
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In question (b),
P = $3000
r = 9%
n = 2
3000 ( 1 + 9/100) ^2 = $6270