conversations.from: human
conversations.value: Donny went to the gas station to gas up his tank. He knows his truck holds 150 liters of fuel. His truck already contained 38 liters. How much change will he get from $350 if each liter of fuel costs $3?
  What is the solution?
conversations.from: assistant
conversations.value: He needs 150 - 38 = 112 liters more to have a full tank of gas.
  Donny will pay 112 x $3 = $336 for a full tank of gas.
  His will get $350 - $336 = $14 change."