20% is the change from 285 to 342
Calculation steps:
[( 342 - 285 ) ÷ 285] x 100 = 20%
Formula
Percentage change = [(342 - 285) / 285] x 100
Subtract the new number by the original number
342 - 285 = 57
57 ÷ 285 = 0.2
0.2 x 100 = 20%
Example