30.61% is the change from 49 to 64
Calculation steps:
[( 64 - 49 ) ÷ 49] x 100 = 30.61%
Formula
Percentage change = [(64 - 49) / 49] x 100
Subtract the new number by the original number
64 - 49 = 15
15 ÷ 49 = 0.30612244897959184
0.30612244897959184 x 100 = 30.61%