The total mass of 5 boxes and 6 tanks was 42.8 kg.
The total mass of 4 boxes and 4 tanks was 30.4 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 = 42.8 --- (1)
4 boxes + 4 tanks = 30.4 --- (2)
(2)
÷ 4 1 box + 1 tank = 7.6 --- (3)
Mass of 1 box and 1 tank = 7.6 kg
(b)
(3) x 5
5 boxes + 5 tanks = 5 x 7.6
5 boxes + 5 tanks = 38 --- (4)
(1) - (4)
(5 boxes + 6 tanks) - (5 boxes + 5 tanks) = 42.8 - 38
5 boxes - 5 boxes + 6 tanks - 5 tanks = 4.8
1 tank = 4.8
10 tanks = 4.8 x 10 = 48
Mass of 10 tanks = 48 kg
(c)
Substitute 1 tank = 4.8 into (3).
1 box + 1 tank = 7.6
1 box + 4.8 = 7.6
1 box = 7.6 - 4.8 = 2.8
Mass of 1 box = 2.8 kg
Mass of 1 box less than 1 tank
= 4.8 - 2.8
= 2 kg
Answer(s): (a) 7.6 kg; (b) 48 kg; (c) 2 kg