107.75% is the change from 400 to 831
Calculation steps:
[( 831 - 400 ) ÷ 400] x 100 = 107.75%
Formula
Percentage change = [(831 - 400) / 400] x 100
Subtract the new number by the original number
831 - 400 = 431
431 ÷ 400 = 1.0775
1.0775 x 100 = 107.75%