conversations.from: human
conversations.value: Break down this math problem: Brody’s calculator can run for 60 hours on a full battery. Brody has used three quarters of its battery up, and he is about to take a two-hour math exam that will require his calculator the whole time. How many hours of battery will Brody’s calculator have left?
conversations.from: assistant
conversations.value: Brody’s calculator has 60 * 1/4 = 60 / 4 = 15 hours of battery left.
  After his 2-hour math exam, Brody’s calculator will have 15 - 2 = 13 hours of battery left.