conversations.from: human
conversations.value: Tom bought 10 packages of miniature racing cars. Each package contains five cars. He gave each of his two nephews 1/5 of the cars. How many miniature racing cars are left with Tom?
  Give me a clear explanation.
conversations.from: assistant
conversations.value: Tom had 10 x 5 = 50 miniature racing cars.
  Tom gave 50 x 1/5 = 10 miniature racing cars to each of his two nephews.
  So, he gave a total of 10 x 2 = 20 cars to his two nephews.
  Therefore, Tom is left with 50 - 20 = 30 miniature racing cars.