Exercise
Nov 18'23
Answer
Solution: B
The monthly interest rate is
[[math]]
j = (1.08)^{1/12}-1 = 0.643\%.
[[/math]]
Then,
[[math]]
20.000S_{\overline{3}|0.08}=X \ddot{s}_{\overline{252}|0.00643}\quad90,122.24=630.99X,\quad X=142.83.
[[/math]]
Jennifer establishes an investment account to pay for college expenses for her daughter. She plans to invest X at the beginning of each month for the next 21 years. Beginning at the end of the 18th year, she will withdraw 20,000 annually. The final withdrawal at the end of the 21st year will exhaust the account. She anticipates earning an annual effective yield of 8% on the investment.
Calculate X.
Solution: B
The monthly interest rate is
Then,