conversations.from: human
conversations.value: Explain how to solve this math problem: Max has a collection of stamps in three colors: 20 red stamps, 80 blue stamps and 7 yellow ones. He is trying to sell the whole collection. He already sold 20 red stamps for the price of $1.1 for each stamp and 80 blue stamps for the price of $0.8 for each stamp. What price did he need to set for each yellow stamp to be able to earn the total of $100 from the whole sale?
conversations.from: assistant
conversations.value: Max earned 20 * 1.1 = $22 on red stamps.
  From the blue stamps Max got 80 * 0.8 = $64.
  His earnings so far are 22 + 64 = $86.
  To earn $100 he needs 100 – 86 = $14 more.
  Max has 7 yellow stamps, so he needs to set the price at 14 / 7 = $2.