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?
Earl was on the 1 + 5 = 
<gadget id="calculator">1+5</gadget>
<output>6</output>
6th floor after going up 5 floors.
When he went down 2 floors, he was on the 6 - 2 = 
<gadget id="calculator">6-2</gadget>
<output>4</output>
4th floor.
Since he went up 7 floors, he was then on the 4 + 7 = 
<gadget id="calculator">4+7</gadget>
<output>11</output>
11th floor.
Since he is 9 floors away from the top of the building, therefore the building has 11 + 9 = 
<gadget id="calculator">11+9</gadget>
<output>20</output>
20 floors.

<result>20</result>