The total mass of 5 tanks and 6 boxes was 35.7 kg.
The total mass of 4 tanks and 4 boxes was 25.2 kg.
- What is the mass of 1 tank and 1 box?
- What is the mass of 5 boxes?
- How much less is the mass of 1 box than 1 tank?
(a)
5 tanks + 6 boxes = 35.7 --- (1)
4 tanks + 4 boxes = 25.2 --- (2)
(2)
÷ 4 1 tank + 1 box = 6.3 --- (3)
Mass of 1 tank and 1 box = 6.3 kg
(b)
(3) x 5
5 tanks + 5 boxes = 5 x 6.3
5 tanks + 5 boxes = 31.5 --- (4)
(1) - (4)
(5 tanks + 6 tanks) - (5 tanks + 5 tanks) = 35.7 - 31.5
5 tanks - 5 tanks + 6 boxes - 5 boxes = 4.2
1 box = 4.2
5 boxes = 4.2 x 5 = 21
Mass of 5 boxes = 21 kg
(c)
Substitute 1 box = 4.2 into (3).
1 tank + 1 box = 6.3
1 tank + 4.2 = 6.3
1 tank = 6.3 - 4.2 = 2.1
Mass of 1 tank = 2.1 kg
Mass of 1 tank less than 1 box
= 4.2 - 2.1
= 2.1 kg
Answer(s): (a) 6.3 kg; (b) 21 kg; (c) 2.1 kg