conversations.from: human
conversations.value: I would love to understand how to solve this problem: The government donated tons of sand to four Cities. City A received 16 1/2 tons of sand, City B received 26 tons of sand, and City C received 24 1/2 tons of sand. The supplier lost the data for City D; however, they know the total for all four cities was 95 tons. How many tons of sand did City D receive?
  Can you explain?
conversations.from: assistant
conversations.value: The total tons of sand donated to City A and City C is 16 1/2 + 24 1/2 = 41.
  The total tons of sand donated to City A, City B, and City C is 41 + 26 = 67.
  Therefore, City D received 95 - 67 = 28 tons of sand.