170% is the change from 50 to 135
Calculation steps:
[( 135 - 50 ) ÷ 50] x 100 = 170%
Formula
Percentage change = [(135 - 50) / 50] x 100
Subtract the new number by the original number
135 - 50 = 85
85 ÷ 50 = 1.7
1.7 x 100 = 170%
Example