Measuring 7 litres
There are 2 jugs with 4 litres and 5 litres of water respectively. The objective is to pour exactly 7 litres of water in a bucket.
How can this be done?
Initially fill the 5L jug with water and empty the same into the 4L jug.
The 5L jug will be left with 1L of water, which is poured into the bucket. Meanwhile, empty the 4L jug.
The above step is repeated so that the bucket now is filled with 2L of water.
Finally, fill the 5L jug with water and empty the same into the bucket.