Answer: $6000
Explanation:
1) Simple interest means that the interests are calcualted over the original amount borrowed and they are the same every year.
2) yearly interest = interest / number of years = $2400 / 10 = $240
3) the yearly interest equals the amount borrowed times the simple intereset rate:
=> $240 = A * 4%
=> $240 = A * 0.04
=> A = $240 / 0.04 = $6000
You can do the same in one step:
interest = A * simple interest rate * number of years
=> A = interest / [simple interest rate * number of years] = $2400 / [4% * 10]
A = $2400 / (0.04 * 10) = $2400 / 0.4 = $ 6000.
And that is the answer: he borrowed $6000
