conversations.from: human
conversations.value: I'm stuck on this math problem: Dean's mother gave him $28 to go to the toy store. Dean bought 6 toy cars and 5 teddy bears. Each toy car cost $2 and each teddy bear cost $1. His mother then feels generous and decides to give him an extra $10. How much money does Dean have left?
  Can you help?
conversations.from: assistant
conversations.value: The cost of the toy cars is 6 cars × $2/car = $12.
  The cost of the teddy bears is 5 bears × $1/bear = $5.
  The total cost of the toys is $12 + $5 = $17.
  Adding the two amounts of money his mother gave him, we find that Dean has $28 + $10 = $38 to spend.
  Dean has $38 − $17 = $21 left.