conversations.from: human
conversations.value: Can you explain how to solve this math problem: Adam went to a store to buy some sweets. He bought 7 candies of type A and 10 candies of type B. One candy of type A costs $0.5, and one candy of type B costs $0.75. How much change did Adam get, if he paid the cashier $15?
conversations.from: assistant
conversations.value: For type A candies Adam needed to pay 7 * 0.5 = $3.5.
  For the other type of candies, Adam needed to pay 10 * 0.75 = $7.5.
  So Adam had to pay 3.5 + 7.5 = $11 in total for his shopping.
  If Adam gave the cashier $15, that means he got 15 - 11 = $4 of change.