The total mass of 5 boxes and 6 tanks was 25.8 kg.
The total mass of 6 boxes and 6 tanks was 27 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)
5 boxes + 6 tanks = 25.8 --- (1)
6 boxes + 6 tanks = 27 --- (2)
(2)
÷ 6 1 box + 1 tank = 4.5 --- (3)
Mass of 1 box and 1 tank = 4.5 kg
(b)
(3) x 5
5 boxes + 5 tanks = 5 x 4.5
5 boxes + 5 tanks = 22.5 --- (4)
(1) - (4)
(5 boxes + 6 tanks) - (5 boxes + 5 tanks) = 25.8 - 22.5
5 boxes - 5 boxes + 6 tanks - 5 tanks = 3.3
1 tank = 3.3
10 tanks = 3.3 x 10 = 33
Mass of 10 tanks = 33 kg
(c)
Substitute 1 tank = 3.3 into (3).
1 box + 1 tank = 4.5
1 box + 3.3 = 4.5
1 box = 4.5 - 3.3 = 1.2
Mass of 1 box = 1.2 kg
Mass of 1 box less than 1 tank
= 3.3 - 1.2
= 2.1 kg
Answer(s): (a) 4.5 kg; (b) 33 kg; (c) 2.1 kg