conversations.from: human
conversations.value: I would love to understand how to solve this problem: Earl started delivering newspapers on the first floor of a condominium building. He then went up 5 floors then went down 2 floors. He again went up 7 floors and found that he is 9 floors away from the top of the building. How many floors does the building have?
  Can you explain?
conversations.from: assistant
conversations.value: Earl was on the 1 + 5 = 6th floor after going up 5 floors.
  When he went down 2 floors, he was on the 6 - 2 = 4th floor.
  Since he went up 7 floors, he was then on the 4 + 7 = 11th floor.
  Since he is 9 floors away from the top of the building, therefore the building has 11 + 9 = 20 floors.