conversations.from: human
conversations.value: Darwin has 600$. He spent 1/3 of it on gas for his car, and 1/4 of what was left on food. How much money did he have left?
  What is the solution?
conversations.from: assistant
conversations.value: 600/3=200$ for gas
  After buying gas, Darwin has 600-200=400$ left
  400/4=100$ on food
  Darwin has 400-100=300$ left