The total mass of 2 tanks and 3 boxes was 16.5 kg.
The total mass of 6 tanks and 6 boxes was 35.4 kg.
- What is the mass of 1 tank and 1 box?
- What is the mass of 9 boxes?
- How much less is the mass of 1 box than 1 tank?
(a)
2 tanks + 3 boxes = 16.5 --- (1)
6 tanks + 6 boxes = 35.4 --- (2)
(2)
÷ 6 1 tank + 1 box = 5.9 --- (3)
Mass of 1 tank and 1 box = 5.9 kg
(b)
(3) x 2
2 tanks + 2 boxes = 2 x 5.9
2 tanks + 2 boxes = 11.8 --- (4)
(1) - (4)
(2 tanks + 3 tanks) - (2 tanks + 2 tanks) = 16.5 - 11.8
2 tanks - 2 tanks + 3 boxes - 2 boxes = 4.7
1 box = 4.7
9 boxes = 4.7 x 9 = 42.3
Mass of 9 boxes = 42.3 kg
(c)
Substitute 1 box = 4.7 into (3).
1 tank + 1 box = 5.9
1 tank + 4.7 = 5.9
1 tank = 5.9 - 4.7 = 1.2
Mass of 1 tank = 1.2 kg
Mass of 1 tank less than 1 box
= 4.7 - 1.2
= 3.5 kg
Answer(s): (a) 5.9 kg; (b) 42.3 kg; (c) 3.5 kg