In the old days there were elevator operators to transport passengers. Don Downs always started his day in the basement. He went up 20 floors to take his boss some coffee. Then he went down 8 floors to take a donut to his friend. He went up 7 floors to check things out. This was the halfway point in the building. How many floors are in this building? (FYI: The basement is not considered a floor in this building)

Let x = number of floors

20 - 8 + 7 = .5x

Solve for x.

To determine the total number of floors in the building, we can use the information provided in the question.

First, we know that Don starts his day in the basement and goes up 20 floors to deliver coffee to his boss. Then he goes down 8 floors to deliver a donut to his friend. Finally, he goes up 7 floors to reach the halfway point in the building.

Let's calculate the total distance covered by Don during these three trips.

Starting from the basement, he goes up 20 floors, then down 8 floors, and finally up 7 floors. So the total distance covered is 20 + 8 + 7 = 35 floors.

Since reaching the halfway point in the building took him exactly half of the total floors, we can double the distance to find the total number of floors in the building. Therefore, the total number of floors in this building would be 35 x 2 = 70.

So, there are 70 floors in this building.