Question 2517c

Dec 20, 2016

This is a 25% discount.

Explanation:

We can restate this problem as:

$13 is what percent of$52?

First, lets call the percent we are looking for "p" or p%.

"Percent" or "%" means "out of 100" or "per 100", Therefore p% can be written as $\frac{p}{100}$.

When dealing with percents the word "of" means "times" or "to multiply".

Putting this altogether we can write this equation and solve for $p$ while keeping the equation balanced:

$13 = p/100 xx$52

$13 = ($52p)/100

$13 xx color(red)(100/($52)) = ($52p)/100 xx color(red)(100/($52))

($1300)/($52) = ($52p)/100 xx 100/($52)

(color(green)(cancel(color(black)($)))1300)/(color(green)(cancel(color(black)($)))52) = (color(blue)(cancel(color(black)($52)))p)/color(red)(cancel(color(black)(100))) xx color(red)(cancel(color(black)(100)))/(color(blue)(cancel(color(black)($52))))#

$\frac{1300}{52} = p$

$25 = p$