The total mass of 2 boxes and 3 tanks was 9.3 kg.
The total mass of 4 boxes and 4 tanks was 14.4 kg.
- What is the mass of 1 box and 1 tank?
- What is the mass of 10 tanks?
- How much less is the mass of 1 tank than 1 box?
(a)
2 boxes + 3 tanks = 9.3 --- (1)
4 boxes + 4 tanks = 14.4 --- (2)
(2)
÷ 4 1 box + 1 tank = 3.6 --- (3)
Mass of 1 box and 1 tank = 3.6 kg
(b)
(3) x 2
2 boxes + 2 tanks = 2 x 3.6
2 boxes + 2 tanks = 7.2 --- (4)
(1) - (4)
(2 boxes + 3 tanks) - (2 boxes + 2 tanks) = 9.3 - 7.2
2 boxes - 2 boxes + 3 tanks - 2 tanks = 2.1
1 tank = 2.1
10 tanks = 2.1 x 10 = 21
Mass of 10 tanks = 21 kg
(c)
Substitute 1 tank = 2.1 into (3).
1 box + 1 tank = 3.6
1 box + 2.1 = 3.6
1 box = 3.6 - 2.1 = 1.5
Mass of 1 box = 1.5 kg
Mass of 1 box less than 1 tank
= 2.1 - 1.5
= 0.6 kg
Answer(s): (a) 3.6 kg; (b) 21 kg; (c) 0.6 kg