Final answer:
To find out how much Matt's parents should deposit into his account, we need to calculate the future value of the monthly withdrawals. Using the compound interest formula, we can determine that they should deposit around $2123.65 to cover the withdrawals and earn interest at a rate of 5% per year compounded monthly.
Step-by-step explanation:
To calculate how much Matt's parents should deposit into his account, we need to find the future value of the monthly withdrawals at the given interest rate. The formula for compound interest is:
FV = P(1 + r/n)^(nt)
Where FV is the future value, P is the principal (the amount deposited), r is the interest rate per period (5% in this case), n is the number of times interest is compounded per year (12 for monthly compounding), and t is the number of years. In this case, t is 9 months (September to May), so let's substitute the values into the formula:
FV = P(1 + 0.05/12)^(12 * 9)
FV = P(1.00416)^108
We want the future value to be $250 * 9 = $2250, so we can set up the equation:
$2250 = P(1.00416)^108
We can solve for P using algebra, which gives us:
P = $2250 / (1.00416)^108
Calculating this using a calculator or spreadsheet, we find that Matt's parents should deposit approximately $2123.65 into his account.