Puzzle | Measuring 6L water from 4L and 9L buckets

Suppose you have a 4-litre jug and a 9-litre bucket, both without any measurement markings. How can you measure exactly 6 litres using only these two containers and an unlimited supply of water?

Check if you were right - full answer with solution below.

Solution:

Consider two containers: a 4-litre jug and a 9-litre bucket, and use them to measure exactly 6 litres of water with an unlimited water supply.

• Fill the 9-litre bucket completely.
• Pour water from the 9-litre bucket into the 4-litre jug until it is full.
• Empty the 4-litre jug.
• Pour water from the 9-litre bucket into the 4-litre jug again until it is full.
• Empty the 4-liter jug.
• Pour the remaining 1 liter from the 9-liter bucket into the 4-liter jug.
• Refill the 9-liter bucket completely.
• Pour water from the 9-liter bucket into the 4-liter jug until it is full (it will take 3 liters).
• You are now left with exactly 6- liters in the 9-liter bucket.