The situation in which the magnitude of the total force is greater than the magnitude of each of the individual forces is when "Four people stand on each side of a large box. All four people push the box with the same amount of force."
In this case, all individuals working together add their forces to push the box, resulting in a total force greater than what any single individual could exert. The other scenarios either involve pulling in opposite directions, which would cancel out the forces, or pulling and pushing where the force magnitudes do not add up positively.