conversations.from: human
conversations.value: At Ken's local store, a pound of steak is going for $7. He decides to get two pounds. At the till, he pays using a $20 bill. How much money will he get back?
conversations.from: assistant
conversations.value: 2 pounds of steak will cost Ken 2 * 7 = 14 dollars
  Subtracting that amount from $20 will give 20 - 14 = 6 dollars
  Ken will therefore get 6 dollars back.