As a summer job, Randall Jui can work at the amusement park earning $8.75 an hour for 20 hours a week, or as a busboy in a resta
urant. As a busboy, he would earn $8.00 per hour for the same 20-hour week. How much more would Randall earn at the amusement park than at the restaurant in one week?
You have to apply simple interest formula, I = (P×R×T)/100 where I represent interest amount, P is principle, R is interest rate and T is number of years :