Tag Archives: results

Competition Results – Beat Jacinta’s Brainteaser!

 

Last month we put up a competition where people were challenged to figure out the following brainteaser

rope

You have two pieces of rope which each burn for exactly one hour. The ropes are not made of the same materials as each other, and each rope is not made of the same materials in its length either. Both ropes will catch fire easily, and burn for exactly one hour, but it is possible that (for example) one might take 52 minutes to burn 25% of its length and then 8 minutes to burn the remaining length, you don’t know.
You have no other form of timing device, no phone, no watch, no clock, no sundial, no sun.
You have a few matches in a match box.
How do you measure out exactly 45 minutes?

 

Here are the three entries we received:

Entry by Doug

1)Cut each rope into their own even 60 pieces

2) Light all the ends at once

3) Once the 30 quickest have burnt out will the remaining 90 strands take 45 minutes?

Trev: Loving the creativity Doug – its not the answer we were looking for but I wonder if that might actually work!

 

Entry by Ross

Use your watch?

Trev: You were not allowed to use timepieces buddy – though I admire anyone who blatantly tries to circumnavigate rules 😉

 

Entry by Mark

Light both same time, but 1 both ends that will burn out in 30 mins then light the other end of the 2nd that will burn out 15 mins later.

Trev: Spot on buddy boy – well done!

 

Mark has declined either prize on offer so will just have to buy him a beer when I see him at a mutual friends 40th next month.  Thanks for playing everyone!