Question

What is the percent of change from 25 to 29

Answer 1

well, clearly is 4 :).

now, if we take 25 to be the 100%, what is 4 off of it in percentage?

`\begin{array}{ccll} amount&\%\\ \cline{1-2} 25 & 100\\ 4& x \end{array} \implies \cfrac{25}{4}~~=~~\cfrac{100}{x} \implies 25x=400\implies x=\cfrac{400}{25}\implies x=16`