80% is the change from 280 to 504
Calculation steps:
[( 504 - 280 ) ÷ 280] x 100 = 80%
Formula
Percentage change = [(504 - 280) / 280] x 100
Subtract the new number by the original number
504 - 280 = 224
224 ÷ 280 = 0.8
0.8 x 100 = 80%
Example