50% is the change from 320 to 480
Calculation steps:
[( 480 - 320 ) ÷ 320] x 100 = 50%
Formula
Percentage change = [(480 - 320) / 320] x 100
Subtract the new number by the original number
480 - 320 = 160
160 ÷ 320 = 0.5
0.5 x 100 = 50%
Example