Let the amount of space at the top be x.
The amount of space at the bottom will thus be
2x, and the amount of space in the middle will be 1.5x
Altogether the sum is 4.5
We have:
0.9 = x + 2x + 1.5x
4.5x = 0.9
x = 0.2
The middle shelf have 1.5x = 1.5(0.2) = 0.3m
space
Or an alternative solution:
Divide 0.9 m by 4.5 to see how much meter the unit 1 is:
0.9 / 4.5 = 0.2 m.
The upper space is 0.2 m, the middle space = 0.3 m, the base
space = 0.4 m.
