A and B walk around a circular track.

A and B walk around a circular track. They start at 9 a.m. from the same point in the opposite directions. A and B walk at a speed of 2 rounds per hour and 3 rounds per hour respectively. How many times shall they cross each other before 12:00 P.m.?

Quiz

Answer/Solution

20

Steps/Work

Sol.
Relative speed = (2 + 3) = 5 rounds per hour.
So, they cross each other 5 times in an hour.
Hence, they cross each other 20 times before 12:00 P.m.
Answer E