9 containers and 8 tanks can hold 38.6 litres of water.
1 container and 1 tank can hold 4.5 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 7 tanks hold?
- How many litres of water can 4 tanks and 9 containers?
(a)
9 containers + 8 tanks = 38.6 --- (1)
1 container + 1 tank = 4.5 --- (2)
(2) x 8
1 container + 1 tank = 4.5
8 containers + 8 tanks = 4.5 x 8
8 containers + 8 tanks = 36 --- (3)
(1) - (3)
(9 containers + 8 tanks) - (8 containers + 8 tanks) = 38.6 - 36
9 containers + 8 tanks - 8 containers - 8 tanks = 2.6
9 containers - 8 containers + 8 tanks - 8 tanks = 2.6
1 container = 2.6
Volume of 1 container = 2.6 ℓ
(b)
Substitute 1 container = 2.6 into (2).
1 container + 1 tank = 4.5
2.6 + 1 tank = 4.5
1 tank = 4.5 - 2.6 = 1.9
Volume of 1 tank = 1.9 ℓ
(c)
Volume of 7 tanks
= 7 x 1.9
= 13.3 ℓ
(d)
Volume of 4 tanks and 9 containers
= 4 x 1.9 + 9 x 2.6
= 7.6 + 23.4
= 31 ℓ
Answer(s): (a) 2.6 ℓ; (b) 1.9 ℓ; (c) 13.3 ℓ; (d) 31 ℓ