Question

David saves money from his teaching job to buy a new boat when he retires in 20 years. The boat will cost $30,000. He has $12,000 in his simple interest savings account. To reach his goal by retirement, David should ________.

Answer 1

Invest at a minimum of 7.5% annual simple interest

Step-by-step explanation:

Given the goal of purchasing a boat that will cost $30,000 in 20 years, David needs to earn an interest computed below on his investment in the savings account.

Interest required = 30,000 - 12,000

= 18,000

Therefore the minimum rate of interest that will achieve this goal,

= Principal * rate * time = target amount

= 12,000 * R * 20 years = 18,000

= R = 18,000/(12,000*20) = 0.075 = 7.5%.

In addition, David could also continue his saving from his teaching job. This will reduce the minimum investment return required to achieve the goal.