The ratio 4 to 5 means that the left model should have 4 segments shaded (out of 5 given).
The ratio 9 to 10 means that the right model should have 9 segments shaded (out of 10 given).
Compare the shaded regions. If you draw the horizontal line in the left model. then there will be 8 segments shaded (out of 10), this means the ratio 4 : 5 is less than the ratio 9 : 10.
because it is very much important to first use your money on needs because you're basically cannot live without Me by and then you can spoil yourself by getting wants