120% is the change from 290 to 638
Calculation steps:
[( 638 - 290 ) ÷ 290] x 100 = 120%
Formula
Percentage change = [(638 - 290) / 290] x 100
Subtract the new number by the original number
638 - 290 = 348
348 ÷ 290 = 1.2
1.2 x 100 = 120%
Example