31.25% is the change from 240 to 315
Calculation steps:
[( 315 - 240 ) ÷ 240] x 100 = 31.25%
Formula
Percentage change = [(315 - 240) / 240] x 100
Subtract the new number by the original number
315 - 240 = 75
75 ÷ 240 = 0.3125
0.3125 x 100 = 31.25%
Example