300% is the change from 7 to 28
Calculation steps:
[( 28 - 7 ) ÷ 7] x 100 = 300%
Formula
Percentage change = [(28 - 7) / 7] x 100
Subtract the new number by the original number
28 - 7 = 21
21 ÷ 7 = 3
3 x 100 = 300%
Example