5 containers and 4 pails can hold 51.3 litres of water.
1 container and 1 pail can hold 10.9 litres of water.

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

(a)
5 containers + 4 pails = 51.3 --- (1)
1 container + 1 pail = 10.9 --- (2)

(2) x 4
1 container + 1 pail = 10.9
4 containers + 4 pails = 10.9 x 4
4 containers + 4 pails = 43.6 --- (3)

(1) - (3)
(5 containers + 4 pails) - (4 containers + 4 pails) = 51.3 - 43.6
5 containers + 4 pails - 4 containers - 4 pails = 7.7
5 containers - 4 containers + 4 pails - 4 pails = 7.7

1 container = 7.7

Volume of 1 container = 7.7 ℓ

(b)
Substitute 1 container = 7.7 into (2).
1 container + 1 pail = 10.9
7.7 + 1 pail = 10.9

1 pail = 10.9 - 7.7 = 3.2

Volume of 1 pail = 3.2 ℓ

(c)
Volume of 6 pails
= 6 x 3.2
= 19.2 ℓ

(d)
Volume of 8 pails and 5 containers
= 8 x 3.2 + 5 x 7.7
= 25.6 + 38.5
= 64.1 ℓ

Answer(s): (a) 7.7 ℓ; (b) 3.2 ℓ; (c) 19.2 ℓ; (d) 64.1 ℓ