Question 7
A duck-pond in the local park has a one-mile path right round it. Grandma walked round the pond for an hour at an average speed of 3 miles per hour. Her grandson Jerry started at the same place and time, ran for an hour at an average speed of 8 miles per hour, and went in the opposite direction. How many times did they meet after starting and before the end of their respective exercise? Do not include the final encounter.