Doug and Myra deposit $600.00 into a savings account which earns 5% interest compounded monthly. They want to use the money in the account to go on a trip in 2 years. How much will they be able to spend? . n Use the formula A = P 1 + where A is the balance (final amount), P is the principal (starting mount), r is the interest rate expressed as a decimal, n is the number of times per year that the terest is compounded, and t is the time in years. und your answer to the nearest cent.