Discussion Forum

The inscent stick puzzle; can you solve it?

Zen problem

A Buddhist monk got an errand from his teacher: to meditate for exactly 45 minutes. He has no watch; instead he is given two inscent sticks, and he is told that each of those sticks would completely burn in 1 hour. The sticks are not identical, and they burn with variant yet unknown rates (they are hand-made). So he has these two inscent and some matches: can he arrange for exactly 45 minutes of meditation?
Good job Jago!
The whole meditate for 45 mins part of the question won’t work with all the attention you need to give to the sticks, but nice work everyone on this puzzle.


(Powered by Yahoo Answers)

10 Comment threads
0 Thread replies
0 Followers
 
Most reacted comment
Hottest comment thread
1 Comment authors
captbullshotherbman76saleemK_Patsecret Recent comment authors
  Subscribe  
newest oldest most voted
Notify of
captbullshot
Guest
captbullshot

Inscent?

herbman76
Guest
herbman76

1 stick burn 1 end the other burn 2 ends, then the 1 with 2 end finsihed (30mins) start to burn the other end i.e (15mins) total:45mins

saleem
Guest
saleem

Yes, its quite easy and it can b solved with just one stick.. Take the stick make four equal pieces of it. Now each piece of it will burn in 15 minutes… So burn the three pieces which will take 45 minutes.

K_Pat
Guest
K_Pat

It’s not possible to meditate if he should watch the sticks, it’ very simple, the problem is not mathematic but logical….

secret
Guest
secret

if you light both ends of a stick, it’ll take half as long to burn, no matter how un-uniformly it burns. At the same time you light the end of one stick, light both ends of the other stick. The both-ended-stick will burn out after half an hour (30 minutes). When that happens, the one-ended stick will have 30 minutes left to burn. Light the other end of that stick. When that stick burns out, a further 15 minutes will have elapsed, which means that 45 minutes will have passed since you orignally lit the three ends. or break both… Read more »

zebbedee
Guest
zebbedee

The second answer would be corect if it wasn’t for the monk having to focus on the sticks at around the half hour mark and is therefor not meditating.

Booboo64
Guest
Booboo64

Are they variable rates as in the rate of each stick varies or has each stick got it’s own rate which is different to the other. if it is constant then you wait for one stick to burn half way down then light the other. jargo got well done

Bottom Contributor
Guest
Bottom Contributor

Just meditate for an hour instead.

Jago
Guest
Jago

The trick is that if you light both ends of a stick, it’ll take half as long to burn, no matter how un-uniformly it burns.

At the same time you light the end of one stick, light both ends of the other stick.
The both-ended-stick will burn out after half an hour (30 minutes).
When that happens, the one-ended stick will have 30 minutes left to burn.
Light the other end of that stick.
When that stick burns out, a further 15 minutes will have elapsed, which means that 45 minutes will have passed since you orignally lit the three ends.

civil_av8r
Guest
civil_av8r

yes, break both sticks in half, then he will have 4 30min sticks. if he breaks one of those sticks in half he’ll have 2 15min sticks. then he can burn a 30 min stick and a 15 min stick.