5 tanks and 4 pails can hold 35.9 litres of water.
1 tank and 1 pail can hold 8 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 8 pails and 5 tanks?
(a)
5 tanks + 4 pails = 35.9 --- (1)
1 tank + 1 pail = 8 --- (2)
(2) x 4
1 tank + 1 pail = 8
4 tanks + 4 pails = 8 x 4
4 tanks + 4 pails = 32 --- (3)
(1) - (3)
(5 tanks + 4 pails) - (4 tanks + 4 pails) = 35.9 - 32
5 tanks + 4 pails - 4 tanks - 4 pails = 3.9
5 tanks - 4 tanks + 4 pails - 4 pails = 3.9
1 tank = 3.9
Volume of 1 tank = 3.9 ℓ
(b)
Substitute 1 tank = 3.9 into (2).
1 tank + 1 pail = 8
3.9 + 1 pail = 8
1 pail = 8 - 3.9 = 4.1
Volume of 1 pail = 4.1 ℓ
(c)
Volume of 6 pails
= 6 x 4.1
= 24.6 ℓ
(d)
Volume of 8 pails and 5 tanks
= 8 x 4.1 + 5 x 3.9
= 32.8 + 19.5
= 52.3 ℓ
Answer(s): (a) 3.9 ℓ; (b) 4.1 ℓ; (c) 24.6 ℓ; (d) 52.3 ℓ