The total mass of 5 boxes and 6 tanks was 37.8 kg.
The total mass of 4 boxes and 4 tanks was 26.4 kg.
- What is the mass of 1 box and 1 tank?
- What is the mass of 9 tanks?
- How much less is the mass of 1 tank than 1 box?
(a)
5 boxes + 6 tanks = 37.8 --- (1)
4 boxes + 4 tanks = 26.4 --- (2)
(2)
÷ 4 1 box + 1 tank = 6.6 --- (3)
Mass of 1 box and 1 tank = 6.6 kg
(b)
(3) x 5
5 boxes + 5 tanks = 5 x 6.6
5 boxes + 5 tanks = 33 --- (4)
(1) - (4)
(5 boxes + 6 tanks) - (5 boxes + 5 tanks) = 37.8 - 33
5 boxes - 5 boxes + 6 tanks - 5 tanks = 4.8
1 tank = 4.8
9 tanks = 4.8 x 9 = 43.2
Mass of 9 tanks = 43.2 kg
(c)
Substitute 1 tank = 4.8 into (3).
1 box + 1 tank = 6.6
1 box + 4.8 = 6.6
1 box = 6.6 - 4.8 = 1.8
Mass of 1 box = 1.8 kg
Mass of 1 box less than 1 tank
= 4.8 - 1.8
= 3 kg
Answer(s): (a) 6.6 kg; (b) 43.2 kg; (c) 3 kg