perplexus.info :: General : Circular Jogging Track Problem

Circular Jogging Track Problem (Posted on 2006-04-12)

Three friends A, B and C regularly jog in circular jogging track every morning. The track is 1000 m in circumference.

A takes 8 mins to complete one lap, B takes 10 mins and 40 secs and C takes 12 mins. One day they decided to find out if they set out together in the same direction from a point what would be the fastest time for all of them to meet at any point on the track. What did they conclude?

The second day C decides to run in the opposite direction from the starting point. When will they all meet? Will this be sooner than the time taken on day one? Where do they meet in both cases?

Submitted by Salil

No Rating

Solution: (Hide)

By calculating time taken using differential speed every 32 mins A & B meet & every 24 mins A & C meet. The LCM of the two is 96 mins. In the second case it is LCM of 32 min & 4.8 mins which is same 96mins. In both cases meeting point is the starting point.

Comments: ( You must be logged in to post comments.)

Subject	Author	Date
Explanation to Puzzle Answer	K Sengupta	2022-05-20 00:59:53
Puzzle Answer	K Sengupta	2022-05-19 00:03:53
circular jogging track problem	hugh	2006-04-18 23:52:58
Near miss on day two	Jer	2006-04-13 13:38:00
re(2): Wait a minute.	Leming	2006-04-13 08:15:05
re: Wait a minute.	vilnius	2006-04-12 21:13:47
Wait a minute.	vilnius	2006-04-12 21:11:22
re(2): A start?	Dej Mar	2006-04-12 11:23:22
re(2): A start?	tomarken	2006-04-12 11:01:34
re: A start?	Charlie	2006-04-12 10:49:51
A start?	tomarken	2006-04-12 09:56:18

Please log in:

Login:
Password:
Remember me:

Sign up! \| Forgot password

Search:

Search body:

Forums (1)
Newest Problems
Random Problem
FAQ | About This Site
Site Statistics
New Comments (6)
Unsolved Problems
Top Rated Problems
This month's top
Most Commented On

Chatterbox:


perplexus dot info