Answer:
3 floors.
Step-by-step explanation:
We have been given that an elevator goes up 7 floors.
We know that going up is a positive altitude, so 7 floors up will be positive 7.
Then the elevator comes down 4 floors. We know that coming down is a negative altitude, so coming down 4 floors would be
floors.
The change in the floor would be
floors.
Therefore, the change in the floor level is 3 floors.