9514 1404 393
Answer:
105 steps
Explanation:
John makes up the distance by 2 steps for each 7 steps he takes. He will need to take 15×7 = 105 steps to gain 15×2 = 30 steps on John.
Meanwhile, Henry is taking 15×5 = 75 steps.
John must take 105 steps to overtake Henry.
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The answer is obtained by comparing the rate of decrease of separation to the total separation that must be decreased.