4 tanks and 3 pails can hold 37.5 litres of water.
1 tank and 1 pail can hold 9.7 litres of water.
- How many litres of water can 1 tank hold?
- How many litres of water can 1 pail hold?
- How many litres of water can 6 pails hold?
- How many litres of water can 7 pails and 4 tanks?
(a)
4 tanks + 3 pails = 37.5 --- (1)
1 tank + 1 pail = 9.7 --- (2)
(2) x 3
1 tank + 1 pail = 9.7
3 tanks + 3 pails = 9.7 x 3
3 tanks + 3 pails = 29.1 --- (3)
(1) - (3)
(4 tanks + 3 pails) - (3 tanks + 3 pails) = 37.5 - 29.1
4 tanks + 3 pails - 3 tanks - 3 pails = 8.4
4 tanks - 3 tanks + 3 pails - 3 pails = 8.4
1 tank = 8.4
Volume of 1 tank = 8.4 ℓ
(b)
Substitute 1 tank = 8.4 into (2).
1 tank + 1 pail = 9.7
8.4 + 1 pail = 9.7
1 pail = 9.7 - 8.4 = 1.3
Volume of 1 pail = 1.3 ℓ
(c)
Volume of 6 pails
= 6 x 1.3
= 7.8 ℓ
(d)
Volume of 7 pails and 4 tanks
= 7 x 1.3 + 4 x 8.4
= 9.1 + 33.6
= 42.7 ℓ
Answer(s): (a) 8.4 ℓ; (b) 1.3 ℓ; (c) 7.8 ℓ; (d) 42.7 ℓ