題組內容

5. Mike is 40 years of age and his salary next year will be $85,000. Mike forecasts that his salary will increase at a steady rate at 5% per annum until his retirement at 50.

(2) If Mike saves \( 5\% \) of his salary each year and invests these savings at the interest rate of \( 4\% \), how much will he have saved by age 50? (4分)