Question

Two cyclists are travelling on a highway which has milestones at every kilometer. Cyclist a takes alternatively 7 minutes and 5 minutes between successive milestones while b takes alternatively 4 minutes and 9 minutes. If they both start from the same milestone at the same time and travel in the same direction, how many times do they meet in all after they start?

Answer 1

Answer:

6 times they cross each other.

Step-by-step explanation:

Cyclist A takes 7 minutes and 5 minutes alternatively for each milestone.

Cyclist B takes 4 minutes and 9 minutes alternatively for each mile stone.

A takes 12 minutes for 2 KM, 13 minutes for 2 KM.

So over the time, A goes ahead and B could never cross A.

But initially, B crosses A because, B takes 4 minutes for 1KM alternatively.

Until their gap increases more than 4 minutes, they keep crossing.

Following is the cumulative times A and B cross until they cross.

A-7-12-19-24-31-36-43-----48------55

B-4-13-17-26-30-39-43-----52------56

The bold section is where they cross each other.

So that is 6 times they cross each other.