The total mass of 4 boxes and 5 tanks was 28.6 kg.
The total mass of 6 boxes and 6 tanks was 36 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)
4 boxes + 5 tanks = 28.6 --- (1)
6 boxes + 6 tanks = 36 --- (2)
(2)
÷ 6 1 box + 1 tank = 6 --- (3)
Mass of 1 box and 1 tank = 6 kg
(b)
(3) x 4
4 boxes + 4 tanks = 4 x 6
4 boxes + 4 tanks = 24 --- (4)
(1) - (4)
(4 boxes + 5 tanks) - (4 boxes + 4 tanks) = 28.6 - 24
4 boxes - 4 boxes + 5 tanks - 4 tanks = 4.6
1 tank = 4.6
8 tanks = 4.6 x 8 = 36.8
Mass of 8 tanks = 36.8 kg
(c)
Substitute 1 tank = 4.6 into (3).
1 box + 1 tank = 6
1 box + 4.6 = 6
1 box = 6 - 4.6 = 1.4
Mass of 1 box = 1.4 kg
Mass of 1 box less than 1 tank
= 4.6 - 1.4
= 3.2 kg
Answer(s): (a) 6 kg; (b) 36.8 kg; (c) 3.2 kg