conversations.from: human
conversations.value: Nancy bought a pie sliced it into 8 pieces. She gave 1/2 to Joe and Darcy, and she gave 1/4 to Carl. How many slices were left?
  Solve it.
conversations.from: assistant
conversations.value: The total number of slices she gave to Joe and Darcy is 1/2 x 8 = 4.
  The total slice she gave to Carl is 1/4 x 8 = 2.
  Therefore, the total slices left is 8 - 4 - 2 = 2.