290% is the change from 10 to 39
Calculation steps:
[( 39 - 10 ) ÷ 10] x 100 = 290%
Formula
Percentage change = [(39 - 10) / 10] x 100
Subtract the new number by the original number
39 - 10 = 29
29 ÷ 10 = 2.9
2.9 x 100 = 290%
Example