conversations.from: human
conversations.value: Andrea needs 45 rhinestones to finish an art project. She bought a third of what she needed and found a fifth of what she needed in her supplies. How many rhinestones does she still need?
  Solve this problem.
conversations.from: assistant
conversations.value: Andrea bought 45 / 3 = 15 rhinestones.
  She found 45 / 5 = 9 rhinestones in her supplies.
  Thus, Andrea still needs 45 - 15 - 9 = 21 rhinestones.