5 pails and 4 tanks can hold 40.4 litres of water.
1 pail and 1 tank can hold 9 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 5 tanks hold?
- How many litres of water can 9 tanks and 5 pails?
(a)
5 pails + 4 tanks = 40.4 --- (1)
1 pail + 1 tank = 9 --- (2)
(2) x 4
1 pail + 1 tank = 9
4 pails + 4 tanks = 9 x 4
4 pails + 4 tanks = 36 --- (3)
(1) - (3)
(5 pails + 4 tanks) - (4 pails + 4 tanks) = 40.4 - 36
5 pails + 4 tanks - 4 pails - 4 tanks = 4.4
5 pails - 4 pails + 4 tanks - 4 tanks = 4.4
1 pail = 4.4
Volume of 1 pail = 4.4 ℓ
(b)
Substitute 1 pail = 4.4 into (2).
1 pail + 1 tank = 9
4.4 + 1 tank = 9
1 tank = 9 - 4.4 = 4.6
Volume of 1 tank = 4.6 ℓ
(c)
Volume of 5 tanks
= 5 x 4.6
= 23 ℓ
(d)
Volume of 9 tanks and 5 pails
= 9 x 4.6 + 5 x 4.4
= 41.4 + 22
= 63.4 ℓ
Answer(s): (a) 4.4 ℓ; (b) 4.6 ℓ; (c) 23 ℓ; (d) 63.4 ℓ