9 pails and 8 tanks can hold 41.5 litres of water.
1 pail and 1 tank can hold 4.8 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 3 tanks hold?
- How many litres of water can 4 tanks and 9 pails?
(a)
9 pails + 8 tanks = 41.5 --- (1)
1 pail + 1 tank = 4.8 --- (2)
(2) x 8
1 pail + 1 tank = 4.8
8 pails + 8 tanks = 4.8 x 8
8 pails + 8 tanks = 38.4 --- (3)
(1) - (3)
(9 pails + 8 tanks) - (8 pails + 8 tanks) = 41.5 - 38.4
9 pails + 8 tanks - 8 pails - 8 tanks = 3.1
9 pails - 8 pails + 8 tanks - 8 tanks = 3.1
1 pail = 3.1
Volume of 1 pail = 3.1 ℓ
(b)
Substitute 1 pail = 3.1 into (2).
1 pail + 1 tank = 4.8
3.1 + 1 tank = 4.8
1 tank = 4.8 - 3.1 = 1.7
Volume of 1 tank = 1.7 ℓ
(c)
Volume of 3 tanks
= 3 x 1.7
= 5.1 ℓ
(d)
Volume of 4 tanks and 9 pails
= 4 x 1.7 + 9 x 3.1
= 6.8 + 27.9
= 34.7 ℓ
Answer(s): (a) 3.1 ℓ; (b) 1.7 ℓ; (c) 5.1 ℓ; (d) 34.7 ℓ