Question

A and b move clockwise around a circle, starting from a common point o. A takes 9 minutes tocomplete a round but re-starts after a delay of 1 minute. B takes 13 minutes to complete theround but restarts after a delay of 2 minutes. How many minutes after they began would theymeet again at o

Answer 1

Answer:

Step-by-step explanation:

Total time taken by A for completion of 1 rotation is 9+1=10 minutes;

Time taken by B for completion of 1 rotation is 13+2=15 minutes:

So the LCM of 10 and 15 is 30;

It means after 30 minutes they will meet again or 60,90,120.. At that time they will meet

Answer 2

Answer:

30  minutes after they began would theymeet again at o

Step-by-step explanation:

It is given that,

A takes 9 minutes to complete a round but re-starts after a delay of 1 minute.

Therefore A take 9 + 1 = 10 minutes to complete one cycle

B takes 13 minutes to complete the round but restarts after a delay of 2 minutes.

Therefore B take 13 + 2 = 15  minutes to complete the cycle.

To find the meeting time

So we have to find the LCM of 10 and 15

LCM(10, 15 ) = 30

Therefore after each 30 minutes they meet

First meets at 30 minutes , then they again meets after 60, 90,120 minutes ...