7 containers and 6 tanks can hold 75.5 litres of water.
1 container and 1 tank can hold 11.1 litres of water.
- How many litres of water can 1 container hold?
- How many litres of water can 1 tank hold?
- How many litres of water can 9 tanks hold?
- How many litres of water can 9 tanks and 7 containers?
(a)
7 containers + 6 tanks = 75.5 --- (1)
1 container + 1 tank = 11.1 --- (2)
(2) x 6
1 container + 1 tank = 11.1
6 containers + 6 tanks = 11.1 x 6
6 containers + 6 tanks = 66.6 --- (3)
(1) - (3)
(7 containers + 6 tanks) - (6 containers + 6 tanks) = 75.5 - 66.6
7 containers + 6 tanks - 6 containers - 6 tanks = 8.9
7 containers - 6 containers + 6 tanks - 6 tanks = 8.9
1 container = 8.9
Volume of 1 container = 8.9 ℓ
(b)
Substitute 1 container = 8.9 into (2).
1 container + 1 tank = 11.1
8.9 + 1 tank = 11.1
1 tank = 11.1 - 8.9 = 2.2
Volume of 1 tank = 2.2 ℓ
(c)
Volume of 9 tanks
= 9 x 2.2
= 19.8 ℓ
(d)
Volume of 9 tanks and 7 containers
= 9 x 2.2 + 7 x 8.9
= 19.8 + 62.3
= 82.1 ℓ
Answer(s): (a) 8.9 ℓ; (b) 2.2 ℓ; (c) 19.8 ℓ; (d) 82.1 ℓ