Answer :

[tex]p\% \ of \ 48=15 \\\\ \frac{p}{100}*48=15 \\\\ \frac{p}{100}=\frac{15}{48} \\\\ \frac{p}{100}=\frac{5}{16} \\\\ p=\frac{100*5}{16} \\\\ p=\frac{25*5}{4} \\\\ p=6.25*5\\\\ \boxed{p=31.25\%}[/tex]
The way to do this is to divide the two numbers (15 and 48) and then multiply the answer by 100.

So.. (15 / 48) * 100 = your answer

Or you can do it the long way, which is how I do it.  You can divide 100 by 48, and then multiply it by 15.

So... (100 / 48) * 15 = your answer