The total mass of 3 boxes and 4 tanks was 29.2 kg.
The total mass of 4 boxes and 4 tanks was 32.4 kg.
- What is the mass of 1 box and 1 tank?
- What is the mass of 5 tanks?
- How much less is the mass of 1 tank than 1 box?
(a)
3 boxes + 4 tanks = 29.2 --- (1)
4 boxes + 4 tanks = 32.4 --- (2)
(2)
÷ 4 1 box + 1 tank = 8.1 --- (3)
Mass of 1 box and 1 tank = 8.1 kg
(b)
(3) x 3
3 boxes + 3 tanks = 3 x 8.1
3 boxes + 3 tanks = 24.3 --- (4)
(1) - (4)
(3 boxes + 4 tanks) - (3 boxes + 3 tanks) = 29.2 - 24.3
3 boxes - 3 boxes + 4 tanks - 3 tanks = 4.9
1 tank = 4.9
5 tanks = 4.9 x 5 = 24.5
Mass of 5 tanks = 24.5 kg
(c)
Substitute 1 tank = 4.9 into (3).
1 box + 1 tank = 8.1
1 box + 4.9 = 8.1
1 box = 8.1 - 4.9 = 3.2
Mass of 1 box = 3.2 kg
Mass of 1 box less than 1 tank
= 4.9 - 3.2
= 1.7 kg
Answer(s): (a) 8.1 kg; (b) 24.5 kg; (c) 1.7 kg