Question

Which situation involves a change modeled by a positive number but an end result modeled by a negative number?

Leo enters an elevator on the second floor and goes down four floors.

A plane, flying at an altitude of 300 feet, descends 50 feet.

Irene is scuba diving at –30 feet. She swims 10 feet toward the surface to watch a school of fish.

April owes her brother $5. On Friday, she gets $10 for her allowance.

Answer 1

April owes her brother $5. On Friday, she gets $10 for her allowance.

Answer 2

Answer 3, because she swims upward 10 feet (positive change of depth) but she is still 20 feet below the surface at the end.