8 tanks and 7 containers can hold 49.4 litres of water.
1 tank and 1 container can hold 6.7 litres of water.
- How many litres of water can 1 tank hold?
- How many litres of water can 1 container hold?
- How many litres of water can 9 containers hold?
- How many litres of water can 6 containers and 8 tanks?
(a)
8 tanks + 7 containers = 49.4 --- (1)
1 tank + 1 container = 6.7 --- (2)
(2) x 7
1 tank + 1 container = 6.7
7 tanks + 7 containers = 6.7 x 7
7 tanks + 7 containers = 46.9 --- (3)
(1) - (3)
(8 tanks + 7 containers) - (7 tanks + 7 containers) = 49.4 - 46.9
8 tanks + 7 containers - 7 tanks - 7 containers = 2.5
8 tanks - 7 tanks + 7 containers - 7 containers = 2.5
1 tank = 2.5
Volume of 1 tank = 2.5 ℓ
(b)
Substitute 1 tank = 2.5 into (2).
1 tank + 1 container = 6.7
2.5 + 1 container = 6.7
1 container = 6.7 - 2.5 = 4.2
Volume of 1 container = 4.2 ℓ
(c)
Volume of 9 containers
= 9 x 4.2
= 37.8 ℓ
(d)
Volume of 6 containers and 8 tanks
= 6 x 4.2 + 8 x 2.5
= 25.2 + 20
= 45.2 ℓ
Answer(s): (a) 2.5 ℓ; (b) 4.2 ℓ; (c) 37.8 ℓ; (d) 45.2 ℓ