The total mass of 3 boxes and 4 tanks was 19.2 kg.
The total mass of 5 boxes and 5 tanks was 26 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)
3 boxes + 4 tanks = 19.2 --- (1)
5 boxes + 5 tanks = 26 --- (2)
(2)
÷ 5 1 box + 1 tank = 5.2 --- (3)
Mass of 1 box and 1 tank = 5.2 kg
(b)
(3) x 3
3 boxes + 3 tanks = 3 x 5.2
3 boxes + 3 tanks = 15.6 --- (4)
(1) - (4)
(3 boxes + 4 tanks) - (3 boxes + 3 tanks) = 19.2 - 15.6
3 boxes - 3 boxes + 4 tanks - 3 tanks = 3.6
1 tank = 3.6
9 tanks = 3.6 x 9 = 32.4
Mass of 9 tanks = 32.4 kg
(c)
Substitute 1 tank = 3.6 into (3).
1 box + 1 tank = 5.2
1 box + 3.6 = 5.2
1 box = 5.2 - 3.6 = 1.6
Mass of 1 box = 1.6 kg
Mass of 1 box less than 1 tank
= 3.6 - 1.6
= 2 kg
Answer(s): (a) 5.2 kg; (b) 32.4 kg; (c) 2 kg