The total mass of 2 tanks and 3 boxes was 14.4 kg.
The total mass of 6 tanks and 6 boxes was 32.4 kg.
- What is the mass of 1 tank and 1 box?
- What is the mass of 7 boxes?
- How much less is the mass of 1 box than 1 tank?
(a)
2 tanks + 3 boxes = 14.4 --- (1)
6 tanks + 6 boxes = 32.4 --- (2)
(2)
÷ 6 1 tank + 1 box = 5.4 --- (3)
Mass of 1 tank and 1 box = 5.4 kg
(b)
(3) x 2
2 tanks + 2 boxes = 2 x 5.4
2 tanks + 2 boxes = 10.8 --- (4)
(1) - (4)
(2 tanks + 3 tanks) - (2 tanks + 2 tanks) = 14.4 - 10.8
2 tanks - 2 tanks + 3 boxes - 2 boxes = 3.6
1 box = 3.6
7 boxes = 3.6 x 7 = 25.2
Mass of 7 boxes = 25.2 kg
(c)
Substitute 1 box = 3.6 into (3).
1 tank + 1 box = 5.4
1 tank + 3.6 = 5.4
1 tank = 5.4 - 3.6 = 1.8
Mass of 1 tank = 1.8 kg
Mass of 1 tank less than 1 box
= 3.6 - 1.8
= 1.8 kg
Answer(s): (a) 5.4 kg; (b) 25.2 kg; (c) 1.8 kg