155% is the change from 20 to 51
Calculation steps:
[( 51 - 20 ) ÷ 20] x 100 = 155%
Formula
Percentage change = [(51 - 20) / 20] x 100
Subtract the new number by the original number
51 - 20 = 31
31 ÷ 20 = 1.55
1.55 x 100 = 155%
Example