55.56% is the change from 270 to 420
Calculation steps:
[( 420 - 270 ) ÷ 270] x 100 = 55.56%
Formula
Percentage change = [(420 - 270) / 270] x 100
Subtract the new number by the original number
420 - 270 = 150
150 ÷ 270 = 0.5555555555555556
0.5555555555555556 x 100 = 55.56%