The total mass of 5 tanks and 6 boxes was 21.6 kg.
The total mass of 4 tanks and 4 boxes was 15.6 kg.
- What is the mass of 1 tank and 1 box?
- What is the mass of 5 boxes?
- How much less is the mass of 1 box than 1 tank?
(a)
5 tanks + 6 boxes = 21.6 --- (1)
4 tanks + 4 boxes = 15.6 --- (2)
(2)
÷ 4 1 tank + 1 box = 3.9 --- (3)
Mass of 1 tank and 1 box = 3.9 kg
(b)
(3) x 5
5 tanks + 5 boxes = 5 x 3.9
5 tanks + 5 boxes = 19.5 --- (4)
(1) - (4)
(5 tanks + 6 tanks) - (5 tanks + 5 tanks) = 21.6 - 19.5
5 tanks - 5 tanks + 6 boxes - 5 boxes = 2.1
1 box = 2.1
5 boxes = 2.1 x 5 = 10.5
Mass of 5 boxes = 10.5 kg
(c)
Substitute 1 box = 2.1 into (3).
1 tank + 1 box = 3.9
1 tank + 2.1 = 3.9
1 tank = 3.9 - 2.1 = 1.8
Mass of 1 tank = 1.8 kg
Mass of 1 tank less than 1 box
= 2.1 - 1.8
= 0.3 kg
Answer(s): (a) 3.9 kg; (b) 10.5 kg; (c) 0.3 kg