260% is the change from 240 to 864
Calculation steps:
[( 864 - 240 ) ÷ 240] x 100 = 260%
Formula
Percentage change = [(864 - 240) / 240] x 100
Subtract the new number by the original number
864 - 240 = 624
624 ÷ 240 = 2.6
2.6 x 100 = 260%
Example