question: After Andrea saved some money, she then spent the rest of her money on an $11 sweater and gave her brother $4. If she had $36 in the beginning, how much did Andrea save?
answer: Andrea spent and gave her brother a total of $11 + $4 = $<<11+4=15>>15.
  So, she saved $36 - $15 = $<<36-15=21>>21.
  #### 21