8 containers and 7 pails can hold 74.9 litres of water.
1 container and 1 pail can hold 9.9 litres of water.
- How many litres of water can 1 container hold?
- How many litres of water can 1 pail hold?
- How many litres of water can 9 pails hold?
- How many litres of water can 9 pails and 8 containers?
(a)
8 containers + 7 pails = 74.9 --- (1)
1 container + 1 pail = 9.9 --- (2)
(2) x 7
1 container + 1 pail = 9.9
7 containers + 7 pails = 9.9 x 7
7 containers + 7 pails = 69.3 --- (3)
(1) - (3)
(8 containers + 7 pails) - (7 containers + 7 pails) = 74.9 - 69.3
8 containers + 7 pails - 7 containers - 7 pails = 5.6
8 containers - 7 containers + 7 pails - 7 pails = 5.6
1 container = 5.6
Volume of 1 container = 5.6 ℓ
(b)
Substitute 1 container = 5.6 into (2).
1 container + 1 pail = 9.9
5.6 + 1 pail = 9.9
1 pail = 9.9 - 5.6 = 4.3
Volume of 1 pail = 4.3 ℓ
(c)
Volume of 9 pails
= 9 x 4.3
= 38.7 ℓ
(d)
Volume of 9 pails and 8 containers
= 9 x 4.3 + 8 x 5.6
= 38.7 + 44.8
= 83.5 ℓ
Answer(s): (a) 5.6 ℓ; (b) 4.3 ℓ; (c) 38.7 ℓ; (d) 83.5 ℓ