Answer:
144 seconds
Step-by-step explanation:
divide 90 by 15 to get 6
if you are jumping in sets of 15, that means you need to jump 6 sets to get to a total of 90 jumps total. if every set of 15 jumps takes 24 seconds that means that 6 sets will take 144 seconds. 6 x 24 = 144
