Zachary is saving money and plans on making monthly contributions into an account earning an annual interest rate of 4.2%compounded monthly. If Zachary would like to end up with $8,000 after 21 months, how much does he need to contribute to the account every month, to the nearest dollar? Use the following formula to determine your answer.A=d(i(1+i)n−1)A= the future value of the account after n periodsd= the amount invested at the end of each periodi= the interest rate per periodn= the number of periodsAnswer:
Q. Zachary is saving money and plans on making monthly contributions into an account earning an annual interest rate of 4.2% compounded monthly. If Zachary would like to end up with $8,000 after 21 months, how much does he need to contribute to the account every month, to the nearest dollar? Use the following formula to determine your answer.A=d(i(1+i)n−1)A= the future value of the account after n periodsd= the amount invested at the end of each periodi= the interest rate per periodn= the number of periodsAnswer:
Identify Given Values: Identify the given values from the problem.A (future value of the account) = $8,000n (number of periods) = 21 monthsi (interest rate per period) = 4.2% annual interest rate compounded monthlyFirst, we need to convert the annual interest rate to a monthly interest rate by dividing by 12 (since there are 12 months in a year).i = 124.2%i = 120.042i = 0.0035
Convert Annual Rate: Substitute the values into the formula.We have the formula A=d×((1+i)n−1)/i.Now we substitute the values we have into the formula.A=$8,000i=0.0035n=21We need to find d.
Substitute Values: Solve for d using the formula.$8,000=d×((1+0.0035)21−1)/0.0035Now we calculate the right side of the equation step by step.First, calculate (1+i)n:(1+0.0035)21
Solve for d: Calculate the compound factor.(1+0.0035)21≈1.0759Now we subtract 1 from the compound factor.1.0759−1≈0.0759
Calculate Compound Factor: Divide by the interest rate per period.0.0759/0.0035≈21.6857Now we have the denominator of the formula.
Divide by Interest Rate: Solve for the monthly contribution d. $8,000=d×21.6857 Now we divide both sides by 21.6857 to solve for d. d≈$8,000/21.6857 d≈368.85
Solve for Monthly Contribution: Round the monthly contribution to the nearest dollar.Zachary needs to contribute approximately $369 every month.