suppose you have a 4-liter bucket and a 7-liter bucket. you need 5-liters for an aquarium. Explain how to get 5liters if neither bucket is marked?

it is a 7 step process explained in explanation section

Step-by-step explanation:

Step one

fill 7 litre bucket then pour it in 4 liter bucket

output: 7 litre bucket has 3 litres and 4 litres bucket has 4 liter in it

Step two

drain four liter bucket and pour 3 liter from 7 litre bucket in it

output: 7 litre bucket has 0 litres and 4 litres bucket has 3 liter in it

step 3

fill 7 litre bucket and transfer water from it in 4 liter bucket which has already 3 liter in it

output: 7 litre bucket has 6 litres and 4 litres bucket has 4 liter in it

step 4

drain four liter bucket and pour 4 liter from 7 litre bucket which has 6 litre in it

output: 7 litre bucket has 2 litres and 4 litres bucket has 4 liter in it

step 5

drain 4 litre bucket and pour 2 litre from 7 litre bucket

output: 7 litre bucket has 0 litres and 4 litres bucket has 2 liter in it.

step 6

fill 7 liter bucket fully

output: 7 litre bucket has 7 litres and 4 litres bucket has 2 liter in it.

step 7

pour water from 7 liter bucket in 4 litre bucket which has already 2 litre in it

output: 7 litre bucket has 5 litres and 4 litres bucket has 4 liter in it.