Question

Benji borrows $1500 from a friend who charges him 10% interest. He pays the loan back in 18 months. How much interest did Benji owe his friend? Don't put a dollar sign, just enter the number.

Answer 1

It just said his friend charged him 10% interest. It didn’t mention how much he had to pay back over the 18 months. His friend isn’t a bank. 10% of $1,500 is $150. I would think he owed him $150 in total.
He would be a horrible friend if he charged him $2,700 to borrow just $1,500.

Answer 2

The answer is 2,700