Can you answer this? 🤔
4L & 9L
How?
Fill the 9L bottle.
Fill the 4L bottle using the water you filled in the 9L bottle.
By doing this, you now have 5L remaining in the 9L bottle. (9L - 4L)
Now empty out the 4L bottle.
Fill the 4L bottle up with water again using the water you have remaining in the 9L bottle (that is, 5L of water)
By doing this, you now have 1L remaining in the 9L bottle. (5L - 4L)
In other words,
Fill up the 9L bottle. Empty the water into the 4L bottle, twice. You have 1L left.
The importance of remainders!
