The total mass of 2 boxes and 3 tanks was 17.5 kg.
The total mass of 5 boxes and 5 tanks was 32 kg.
- What is the mass of 1 box and 1 tank?
- What is the mass of 8 tanks?
- How much less is the mass of 1 tank than 1 box?
(a)
2 boxes + 3 tanks = 17.5 --- (1)
5 boxes + 5 tanks = 32 --- (2)
(2)
÷ 5 1 box + 1 tank = 6.4 --- (3)
Mass of 1 box and 1 tank = 6.4 kg
(b)
(3) x 2
2 boxes + 2 tanks = 2 x 6.4
2 boxes + 2 tanks = 12.8 --- (4)
(1) - (4)
(2 boxes + 3 tanks) - (2 boxes + 2 tanks) = 17.5 - 12.8
2 boxes - 2 boxes + 3 tanks - 2 tanks = 4.7
1 tank = 4.7
8 tanks = 4.7 x 8 = 37.6
Mass of 8 tanks = 37.6 kg
(c)
Substitute 1 tank = 4.7 into (3).
1 box + 1 tank = 6.4
1 box + 4.7 = 6.4
1 box = 6.4 - 4.7 = 1.7
Mass of 1 box = 1.7 kg
Mass of 1 box less than 1 tank
= 4.7 - 1.7
= 3 kg
Answer(s): (a) 6.4 kg; (b) 37.6 kg; (c) 3 kg