22.5% is the change from 40 to 49
Calculation steps:
[( 49 - 40 ) ÷ 40] x 100 = 22.5%
Formula
Percentage change = [(49 - 40) / 40] x 100
Subtract the new number by the original number
49 - 40 = 9
9 ÷ 40 = 0.225
0.225 x 100 = 22.5%
Example