242.8% is the change from 250 to 857
Calculation steps:
[( 857 - 250 ) ÷ 250] x 100 = 242.8%
Formula
Percentage change = [(857 - 250) / 250] x 100
Subtract the new number by the original number
857 - 250 = 607
607 ÷ 250 = 2.428
2.428 x 100 = 242.8%
Example