question: Gerald works at a daycare that pays him $30 every day. He worked for an entire week and spent a total of $100. How much does he have left?
answer: He earns $30 daily for a week (7 days) for a total earnings of $30*7 = $<<30*7=210>>210
  He spent $100 leaving him with $210-$100 = $110
  #### 110