Answer:
He can run 20 ft in 15 seconds
Explanation:
we need to change yards to ft
3ft = 1yd
100 yds * 3ft/1yd = 300 ft
distance = rate * time
300 ft = rate * 15 seconds
divide by 15 seconds on both sides
300 ft/15 seconds = rate
20 ft/sec
He can run 20 ft in 15 seconds