The total mass of 2 tanks and 3 boxes was 15.1 kg.
The total mass of 4 tanks and 4 boxes was 22.4 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 = 15.1 --- (1)
4 tanks + 4 boxes = 22.4 --- (2)
(2)
÷ 4 1 tank + 1 box = 5.6 --- (3)
Mass of 1 tank and 1 box = 5.6 kg
(b)
(3) x 2
2 tanks + 2 boxes = 2 x 5.6
2 tanks + 2 boxes = 11.2 --- (4)
(1) - (4)
(2 tanks + 3 tanks) - (2 tanks + 2 tanks) = 15.1 - 11.2
2 tanks - 2 tanks + 3 boxes - 2 boxes = 3.9
1 box = 3.9
7 boxes = 3.9 x 7 = 27.3
Mass of 7 boxes = 27.3 kg
(c)
Substitute 1 box = 3.9 into (3).
1 tank + 1 box = 5.6
1 tank + 3.9 = 5.6
1 tank = 5.6 - 3.9 = 1.7
Mass of 1 tank = 1.7 kg
Mass of 1 tank less than 1 box
= 3.9 - 1.7
= 2.2 kg
Answer(s): (a) 5.6 kg; (b) 27.3 kg; (c) 2.2 kg