1
   

set flame to the cords

 
 
Reply Fri 17 Dec, 2004 07:18 pm
We have two pieces of cord. If we put one of their ends on fire, the
first cord takes exactly 10 minutes to burn while the second takes 8
minutes. The cords are very badly hand manufactured so that there is no guarantee that the burning rate is constant throughout the cord length; if we cut the first cord in half, there's no guarantee each half takes 5 minutes to burn. You may only burn the ends, and no cutting is allowed.

Using just these two pieces of cord and a lighter, what times can you measure?

first time you can measure is:

8m short cord (lit on one end)
*========

Whim
  • Topic Stats
  • Top Replies
  • Link to this Topic
Type: Discussion • Score: 1 • Views: 798 • Replies: 1
No top replies

 
markr
 
  1  
Reply Fri 17 Dec, 2004 07:50 pm
4: light both ends of the 8 minute cord
5: both ends of the 10 minute cord
8: one end of the 8
9: both ends of 8, then both ends of 10
10: one end of 10
13: one end of 8, then both ends of 10
14: one end of 10, then both ends of 8
18: one end of 8, then one end of 10

If you don't have to be able to control when the measuring starts, you can subtract to get:
1: light both ends of 8 and 10, start measuring when 8 burns out
2: one end of 8 and 10, start measuring when 8 burns out
3: one end of 8 and both ends of 10, start measuring when 10 burns out
6: one end of 10 and both ends of 8, start measuring when 8 burns out
0 Replies
 
 

Related Topics

Alternative Einstein's riddle answer - Discussion by cedor
Urgent !!! Puzzle / Riddle...Plz helpp - Question by zuzusheryl
Bottle - Question by Megha
"The World's Hardest Riddle" - Discussion by maxlovesmarie
Hard Riddle - Question by retsgned
Riddle Time - Question by Teddy Isaiah
riddle me this (easy) - Question by gree012
Riddle - Question by georgio7
Trick Question I think! - Question by sophocles
Answer my riddle - Question by DanDMan52
 
  1. Forums
  2. » set flame to the cords
Copyright © 2024 MadLab, LLC :: Terms of Service :: Privacy Policy :: Page generated in 0.04 seconds on 07/23/2024 at 12:03:37