5 pails and 4 containers can hold 22.7 litres of water.
1 pail and 1 container can hold 5.1 litres of water.

1. How many litres of water can 1 pail hold?
2. How many litres of water can 1 container hold?
3. How many litres of water can 6 containers hold?
4. How many litres of water can 8 containers and 5 pails?

(a)
5 pails + 4 containers = 22.7 --- (1)
1 pail + 1 container = 5.1 --- (2)

(2) x 4
1 pail + 1 container = 5.1
4 pails + 4 containers = 5.1 x 4
4 pails + 4 containers = 20.4 --- (3)

(1) - (3)
(5 pails + 4 containers) - (4 pails + 4 containers) = 22.7 - 20.4
5 pails + 4 containers - 4 pails - 4 containers = 2.3
5 pails - 4 pails + 4 containers - 4 containers = 2.3

1 pail = 2.3

Volume of 1 pail = 2.3 ℓ

(b)
Substitute 1 pail = 2.3 into (2).
1 pail + 1 container = 5.1
2.3 + 1 container = 5.1

1 container = 5.1 - 2.3 = 2.8

Volume of 1 container = 2.8 ℓ

(c)
Volume of 6 containers
= 6 x 2.8
= 16.8 ℓ

(d)
Volume of 8 containers and 5 pails
= 8 x 2.8 + 5 x 2.3
= 22.4 + 11.5
= 33.9 ℓ

Answer(s): (a) 2.3 ℓ; (b) 2.8 ℓ; (c) 16.8 ℓ; (d) 33.9 ℓ