First, draw a vertical number line and pick a tick mark to represent the middle floor.
Then trace his path, starting at the middle floor and move 4 floors up.
Then move 3 floors down.
Next is 1 floor up.
Last, move 9 floors down to the ground floor.
If you stop on the first floor and there are seven floors
below the middle floor, there should be 7 floors above.
How many floors are there?
Did you work backwards?
Or did you set up a number line?