5 pails and 4 tanks can hold 39.7 litres of water.
1 pail and 1 tank can hold 8.8 litres of water.
- How many litres of water can 1 pail hold?
- How many litres of water can 1 tank hold?
- How many litres of water can 4 tanks hold?
- How many litres of water can 7 tanks and 5 pails?
(a)
5 pails + 4 tanks = 39.7 --- (1)
1 pail + 1 tank = 8.8 --- (2)
(2) x 4
1 pail + 1 tank = 8.8
4 pails + 4 tanks = 8.8 x 4
4 pails + 4 tanks = 35.2 --- (3)
(1) - (3)
(5 pails + 4 tanks) - (4 pails + 4 tanks) = 39.7 - 35.2
5 pails + 4 tanks - 4 pails - 4 tanks = 4.5
5 pails - 4 pails + 4 tanks - 4 tanks = 4.5
1 pail = 4.5
Volume of 1 pail = 4.5 ℓ
(b)
Substitute 1 pail = 4.5 into (2).
1 pail + 1 tank = 8.8
4.5 + 1 tank = 8.8
1 tank = 8.8 - 4.5 = 4.3
Volume of 1 tank = 4.3 ℓ
(c)
Volume of 4 tanks
= 4 x 4.3
= 17.2 ℓ
(d)
Volume of 7 tanks and 5 pails
= 7 x 4.3 + 5 x 4.5
= 30.1 + 22.5
= 52.6 ℓ
Answer(s): (a) 4.5 ℓ; (b) 4.3 ℓ; (c) 17.2 ℓ; (d) 52.6 ℓ