conversations.from: human
conversations.value: I'm stuck on this math problem: Reginald is selling apples. He sells each apple for $1.25. He plans to use his profits to help repair his bike. His bike cost $80 and the repairs cost 25% of what his bike cost. After the repairs are paid for, 1/5 of the money he'd earned remains. How many apples did he sell?
  Can you help?
conversations.from: assistant
conversations.value: The bike repairs cost $20 because 80 x .25 = 20
  Call the amount he earns e. We know that e - 20 = 1/5e
  Therefore 5e - 100 = e
  Therefore, 4e = 100
  Therefore, e = 25
  Therefore, he sold 20 apples because 25 / 1.25 = 20