Marilyn knows that she needs $45,000 for a down payment on a house. she found an investment that earns 3.15% interest compounding monthly. she would like to purchase the home in 5 years. how much should she put in the account now to ensure she has her down payment? $38,450.39 $30,871.96 $44,296.89 $52,665.27 can you explain how to do it? : )

She should save $38,450.39.

The formula for the amount of money in an interest-bearing account that is compounded is



where A is the total amount in the account, p is the amount of principal invested, r is the interest rate as a decimal number, n is the number of times per year interest is compounded, and t is the number of years.  Using our information we have:



Divide both sides: