Martha invested a principal amount of $15,000 into a savings account that earns simple interest at a rate of 4.5% per year. How much money will she earn in interest over 6 years?
First, we need to calculate the annual interest that Martha will earn:
Annual interest = Principal amount x Interest rate
Annual interest = $15,000 x 0.045
Annual interest = $675
Now we can calculate the total interest that Martha will earn over 6 years:
Total interest = Annual interest x Number of years
Total interest = $675 x 6
Total interest = $4,050
Therefore, Martha will earn a total of $4,050 in interest over 6 years.