The total mass of 4 tanks and 5 boxes was 26.7 kg.
The total mass of 5 tanks and 5 boxes was 28.5 kg.
- What is the mass of 1 tank and 1 box?
- What is the mass of 9 boxes?
- How much less is the mass of 1 box than 1 tank?
(a)
4 tanks + 5 boxes = 26.7 --- (1)
5 tanks + 5 boxes = 28.5 --- (2)
(2)
÷ 5 1 tank + 1 box = 5.7 --- (3)
Mass of 1 tank and 1 box = 5.7 kg
(b)
(3) x 4
4 tanks + 4 boxes = 4 x 5.7
4 tanks + 4 boxes = 22.8 --- (4)
(1) - (4)
(4 tanks + 5 tanks) - (4 tanks + 4 tanks) = 26.7 - 22.8
4 tanks - 4 tanks + 5 boxes - 4 boxes = 3.9
1 box = 3.9
9 boxes = 3.9 x 9 = 35.1
Mass of 9 boxes = 35.1 kg
(c)
Substitute 1 box = 3.9 into (3).
1 tank + 1 box = 5.7
1 tank + 3.9 = 5.7
1 tank = 5.7 - 3.9 = 1.8
Mass of 1 tank = 1.8 kg
Mass of 1 tank less than 1 box
= 3.9 - 1.8
= 2.1 kg
Answer(s): (a) 5.7 kg; (b) 35.1 kg; (c) 2.1 kg