can you help me

Question

Father and son run in opposite directions from one point on a circular path. The son's speed is 3 times faster than his father's. The father ran several laps and met his son twenty times .in the same time how many laps did the son run in the same time?

Answer 1

In the time it takes the father to complete one-fourth of the path, the son will have completed three-fourths of the path in the opposite direction (and thus they will meet at this time). Each time they meet, the father will have completed an additional one-fourth of the path. Therefore every four meetings, the father completes one lap.

Since they meet 20 times, and 20/4 = 5, the father runs 5 laps. The son is running three times as fast, and thus will complete 15 laps.