The total mass of 5 tanks and 6 boxes was 38.9 kg.
The total mass of 4 tanks and 4 boxes was 27.2 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)
5 tanks + 6 boxes = 38.9 --- (1)
4 tanks + 4 boxes = 27.2 --- (2)
(2)
÷ 4 1 tank + 1 box = 6.8 --- (3)
Mass of 1 tank and 1 box = 6.8 kg
(b)
(3) x 5
5 tanks + 5 boxes = 5 x 6.8
5 tanks + 5 boxes = 34 --- (4)
(1) - (4)
(5 tanks + 6 tanks) - (5 tanks + 5 tanks) = 38.9 - 34
5 tanks - 5 tanks + 6 boxes - 5 boxes = 4.9
1 box = 4.9
9 boxes = 4.9 x 9 = 44.1
Mass of 9 boxes = 44.1 kg
(c)
Substitute 1 box = 4.9 into (3).
1 tank + 1 box = 6.8
1 tank + 4.9 = 6.8
1 tank = 6.8 - 4.9 = 1.9
Mass of 1 tank = 1.9 kg
Mass of 1 tank less than 1 box
= 4.9 - 1.9
= 3 kg
Answer(s): (a) 6.8 kg; (b) 44.1 kg; (c) 3 kg