308% is the change from 75 to 306
Calculation steps:
[( 306 - 75 ) ÷ 75] x 100 = 308%
Formula
Percentage change = [(306 - 75) / 75] x 100
Subtract the new number by the original number
306 - 75 = 231
231 ÷ 75 = 3.08
3.08 x 100 = 308%
Example