₦airaland Forum

A girl has just a 5 litre and a 3 litre keg for carrying water, but she needs exactly 4 litres of water from a nearby well. How is she going to get exactly 4 litres of water from the 3 litres and 5 litres kegs that she has with her.

not clear.

bidibudi:
A girl has just a 5 litre and a 3 litre keg for carrying water, but she needs exactly 4 litres of water from a nearby well. How is she going to get exactly 4 litres of water from the 3 litres and 5 litres kegs that she has with her.

My instructions to the girl:

1. Fill the 3-litre keg and empty it into the 5-litre keg.
2. Fill the 3-litre keg a second time and fill up the 5-litre keg, taking care to spill no water. You will have exactly 1 litre left in the 3-litre keg after this.
3. Empty the 5-litre keg.
4. Pour the 1-litre of water in the 3-litre keg into the 5-litre keg.
5. Fill the 3-litre keg and empty it into the 5-litre keg.
6. You now have 4 litres of water in the 5-litre keg.
7. To show your gratitude, cook me a good dinner.
8. End.

Genial got it again. Hmmm

Genial! RESPECT.
I figd it out as well but it tuk me some tym.

Thanks - Migines and Aiphie.

Actually, there is another solution.

1. Fill the 5-litre keg and use it to fill the 3-litre keg. You will have 2 litres left in the 5-litre keg.
2. Empty the  3-litre keg and pour the 2 litres from the 5L keg into it.
3. Fill the 5L keg again and use it to fill the 3L keg.
4. You now have 4L left in the 5L keg.