The total mass of 3 tanks and 4 boxes was 28.6 kg.
The total mass of 5 tanks and 5 boxes was 40 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)
3 tanks + 4 boxes = 28.6 --- (1)
5 tanks + 5 boxes = 40 --- (2)
(2)
÷ 5 1 tank + 1 box = 8 --- (3)
Mass of 1 tank and 1 box = 8 kg
(b)
(3) x 3
3 tanks + 3 boxes = 3 x 8
3 tanks + 3 boxes = 24 --- (4)
(1) - (4)
(3 tanks + 4 tanks) - (3 tanks + 3 tanks) = 28.6 - 24
3 tanks - 3 tanks + 4 boxes - 3 boxes = 4.6
1 box = 4.6
7 boxes = 4.6 x 7 = 32.2
Mass of 7 boxes = 32.2 kg
(c)
Substitute 1 box = 4.6 into (3).
1 tank + 1 box = 8
1 tank + 4.6 = 8
1 tank = 8 - 4.6 = 3.4
Mass of 1 tank = 3.4 kg
Mass of 1 tank less than 1 box
= 4.6 - 3.4
= 1.2 kg
Answer(s): (a) 8 kg; (b) 32.2 kg; (c) 1.2 kg