The total mass of 3 tanks and 4 boxes was 16.9 kg.
The total mass of 4 tanks and 4 boxes was 19.2 kg.
- What is the mass of 1 tank and 1 box?
- What is the mass of 6 boxes?
- How much less is the mass of 1 box than 1 tank?
(a)
3 tanks + 4 boxes = 16.9 --- (1)
4 tanks + 4 boxes = 19.2 --- (2)
(2)
÷ 4 1 tank + 1 box = 4.8 --- (3)
Mass of 1 tank and 1 box = 4.8 kg
(b)
(3) x 3
3 tanks + 3 boxes = 3 x 4.8
3 tanks + 3 boxes = 14.4 --- (4)
(1) - (4)
(3 tanks + 4 tanks) - (3 tanks + 3 tanks) = 16.9 - 14.4
3 tanks - 3 tanks + 4 boxes - 3 boxes = 2.5
1 box = 2.5
6 boxes = 2.5 x 6 = 15
Mass of 6 boxes = 15 kg
(c)
Substitute 1 box = 2.5 into (3).
1 tank + 1 box = 4.8
1 tank + 2.5 = 4.8
1 tank = 4.8 - 2.5 = 2.3
Mass of 1 tank = 2.3 kg
Mass of 1 tank less than 1 box
= 2.5 - 2.3
= 0.2 kg
Answer(s): (a) 4.8 kg; (b) 15 kg; (c) 0.2 kg