How to put 4lit res of water in a 5lit re glass. you have a 5lit re glass and 3 lit re glass.?

Question

you have a tap with running water

Answer 1

Fill the 5 glass then pour it into the 3 glass. what you have left over is 2 liters. empty the 3 glass then pour the 2 litres into the 3 glass. Fill the 5 glass then pour from here into the 3 glass until it is full. Now you have 4 liters in the big glass.