Answer:
$30,586
Explanation:
Using an annuity formula, we will compound at 2.9% for 9 years and the money at the end of year 9 will be used to compound at 2.3% for 12 years.
So compounding formula is:
Future Value = Present Value * (1+r)^n
For compounding at 2.9% for 9 years,
Future Value = $18,000 * (1+2.9%)^9 = $23,281
And now using the money at the end of year 9 to compound at 2.3% for 12 years:
Future Value = $23,281 * (1+2.3%)^9 = $30,586
