The answer is b because it is equivalent.
The three numbers are 52, 53, 54.
52+53=105 105+54=159
<span>The two checkpoints are 4,920 ft. apart from each other. The total distance of the race is 15,840 ft. If checkpoint C half the distance between checkpoint B and the end of the race, the distance between Checkpoint B and the end of the race is 9,840 ft. Half of that distance is 4,920 ft.</span>