Consider the question. Lee mows one lawn and charges $33. Last week he mowed 16 lawns and three customers each gave him a $10 tip. How many dollars did Lee earn mowing lawns last week?
 If the answer is '558'; explain the reasoning:
33 * 16 = $528. 3 * 10 = $30. 528 + 30 = $558. Lee earned $558 mowing lawns last week.