Answer:
918.50 in interest over 11 years.
Explanation:
Comment
You have to make an assumption here. The assumption is that this is simple interest.
So if the brother pays 10% each year, he is paying
10/100 * 835 each year in interest
10/100 * 835 = 83.50 every year.
There are 11 years, so the total interest paid is 11 * 83.50 = 918.50 dollars in total.. That's more than what he borrowed!