conversations.from: human
conversations.value: Can you break down the solution for me for this math problem: In a block of flats, there are 120 apartments. 85% of them have at least 1 resident, while 60% of the apartments have at least two residents. How many apartments have only one resident?
conversations.from: assistant
conversations.value: At least one person lives in 85/100 * 120 = 102 apartments.
  At least two persons live in 60/100 * 120 = 72 apartments.
  So in every of the 102 - 72 = 30 apartments, only one person is living.