15% is the change from 280 to 322
Calculation steps:
[( 322 - 280 ) ÷ 280] x 100 = 15%
Formula
Percentage change = [(322 - 280) / 280] x 100
Subtract the new number by the original number
322 - 280 = 42
42 ÷ 280 = 0.15
0.15 x 100 = 15%
Example