Answer and Explanation:
The computation is shown below:
a. The final amount she will have on deposit is
Future value = Present value × {(1 + interest rate)^number of years - 1} ÷ interest rate
= $11,000 × {(1 + 0.05)^15 - 1} ÷ 0.05
= $11,000 × 21.57856359
= $237,364.20
b. The amount at 4% is
Future value = Present value × {(1 + interest rate)^number of years - 1} ÷ interest rate
= $11,000 × {(1 + 0.04)^15 - 1} ÷ 0.04
= $11,000 × 20.02358764
= $220,259.46
c. The losing amount in case when she used her brother-in-law's bank is
= $237,364.20 - $220,259.46
= $17,104.74
We simply applied the above formula
