Question

5 1/4% of what number is 12.6?

Answer 1

bearing in mind that 5¼ is just 5.25 converted to decimal.

let's say the number is "x", thus "x" is the 100%.

12.6 is 5.25%, what is the 100%? namely "x"?

$\bf \begin{array}{ccll} amount&\%\\ \cline{1-2} x&100\\ 12.6&5.25 \end{array}\implies \cfrac{x}{12.6}=\cfrac{100}{5.25}\implies 5.25x=1260 \\\\\\ x=\cfrac{1260}{5.25}\implies x=240$