Final answer:
To determine who will have the most money in their savings account after 10 years, we calculate the future value for each scenario. Diana will have $1,539, Denise will have $9,758.66, and Leslie will have $1,547.58.
Step-by-step explanation:
To determine who will have the most money in their savings account after 10 years, we need to calculate the future value of each account using the given interest rates and compounding intervals.
For Diana, who made a single deposit of $700 with a simple interest rate of 6.7%, the formula to calculate the future value is: FV = P(1 + rt), where FV is the future value, P is the principal amount, r is the interest rate, and t is the time in years. Plugging in the values, we get FV = 700(1 + 0.067 * 10) = $1,539.
For Denise, who made a deposit of $700 every year with a simple interest rate of 6.5%, we can calculate the future value using the formula for the sum of an ordinary annuity: FV = PMT * [(1 + r)^t - 1] / r, where PMT is the annual deposit, r is the interest rate, and t is the time in years. Plugging in the values, we get FV = 700 * [(1 + 0.065)^10 - 1] / 0.065 = $9,758.66.
For Leslie, who made a single deposit of $700 at an annual interest rate of 6.6% compounded monthly, we can use the formula for compound interest: FV = P(1 + r/n)^(nt), where n is the number of compounding periods per year. Plugging in the values, we get FV = 700(1 + 0.066/12)^(12*10) = $1,547.58.