Brain Teasers
Jugs
You've got a 4 liter jug and a 9 liter jug.
You've got a pool of water.
What is the fewest number of steps it takes to come up with exactly 6 liters of water?
No, you cannot pour some water into the 9 liter jug and then guess. Nor can you fill each jug up half way or something. You have to be exact. A step is defined as putting water into a jug (not emptying). For instance, filling the 4 liter jug and then pouring it into the 9 liter jug is 2 steps.
You've got a pool of water.
What is the fewest number of steps it takes to come up with exactly 6 liters of water?
No, you cannot pour some water into the 9 liter jug and then guess. Nor can you fill each jug up half way or something. You have to be exact. A step is defined as putting water into a jug (not emptying). For instance, filling the 4 liter jug and then pouring it into the 9 liter jug is 2 steps.
Hint
It's under 10.Answer
The full answer is as follows:1. Fill up the 9 liter jug from the pool.
2. Fill up the 4 liter jug from the 9 liter jug (leaving 5 liters in the 9 liter jug).
3. Empty the 4 liter jug into the pool and fill it again from the 9 liter jug (leaving 1 liter in the 9 liter jug).
4. Empty the 4 liter jug into the pool and put the 1 liter from the 9 liter jug into the 4 liter.
5. Fill the 9 liter jug from the pool.
6. Fill up the 4 liter jug from the 9 liter jug. There was 1 liter in the 4 liter jug, so 3 liters will fill it. This leaves, in the 9 liter jug, exactly 6 liters.
Hide Hint Show Hint Hide Answer Show Answer
What Next?
View a Similar Brain Teaser...
If you become a registered user you can vote on this brain teaser, keep track of which ones you have seen, and even make your own.
Solve a Puzzle
Comments hidden to avoid spoilers.
Follow Braingle!