Brain Teasers
Measure Exactly 6 Gallons
Using a tap, a nine-gallon container and a four-gallon container, can you measure exactly 6 gallons?
Answer
Here are the contents of the two containers after each stage (A=nine-gallon container, B=four-gallon container) :A B
9 0 fill A
5 4 fill B from A
5 0 empty B
1 4 fill B from A
1 0 empty B
0 1 fill B from A
9 1 fill A
6 4 fill B from A
6 0 empty B
This leaves 6 gallons in container A.
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Comments
No matter how many times I get ths type of question...I can NEVER get the answer. They are fun to try though...Next time I will get it.
Haha, I did NOT get that one. Awesome answer though.
Here's my solution:
A B
0 4 fill B
4 0 fill A from B
4 4 fill B
8 0 fill A from B
8 4 fill B
9 3 fill A from B
0 3 empty A
3 0 fill A from B
3 4 fill B
7 0 fill A from B
7 4 fill B
9 2 fill A from B
0 2 empty A
2 0 fill A from B
2 4 fill B
6 0 fill A from B
Considerably longer than the given solution, but still valid.
A B
0 4 fill B
4 0 fill A from B
4 4 fill B
8 0 fill A from B
8 4 fill B
9 3 fill A from B
0 3 empty A
3 0 fill A from B
3 4 fill B
7 0 fill A from B
7 4 fill B
9 2 fill A from B
0 2 empty A
2 0 fill A from B
2 4 fill B
6 0 fill A from B
Considerably longer than the given solution, but still valid.
this is my opinion
A(9 gallons) B(4 gallons)
A B
9 0
5 4 fill B from A
5 0 empty B
1 4 fill B from A
1 0 empty B
0 1 fill B from A
9 1 fill full A
6 4 Fill B rom A
and you get exactly 6 gallons in container 9 gallons
A(9 gallons) B(4 gallons)
A B
9 0
5 4 fill B from A
5 0 empty B
1 4 fill B from A
1 0 empty B
0 1 fill B from A
9 1 fill full A
6 4 Fill B rom A
and you get exactly 6 gallons in container 9 gallons
i think there was something like that in one of the Die-Hard movies
great job
i would just full 4 gallon halfway 3 times, pouring each half into 9 gallon
I did it the same way as dragoon and kwelchans
I got the sense of the answer but I don't really know what a tap is.
Can anyone tell me?
Can anyone tell me?
A tap is a faucet...
Very nice teaser
Very nice teaser
I'd fill the 9 gallon one until it reaches the 6 gallon line. But I got the REAL answer.
Shadows, what makes you think there IS a 6-gallon line on the 9-gallon container? Maybe there aren't any lines at all.
this was in die hard 3 and i could never figure it out.
very cool/clever.
very cool/clever.
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