Question

at a sale search were sold for $15 each. This price was 80% of the original price. What was the original price?

Answer 1

Let's say the original price was "x", thus "x" is the 100%, and we know that 15 is 80% of that, thus

$\bf \begin{array}{ccll} amount&\%\\ \text{\textemdash\textemdash\textemdash}&\text{\textemdash\textemdash\textemdash}\\ x&100\\ 15&80 \end{array}\cfrac{x}{15}=\cfrac{100}{80}\implies x=\cfrac{1500}{80}$

Answer 2

The original price was $75.

$15 would be 1/5 (80%) of an uknown number, which is stated in the question. Since it's 1/5, you would multiply 15 by 5, to get 5/5 (100%), which is the original price. To check this, you would take 80% percent from 75 (0.8*75), which gives you 15. Thus proving $75 dollars was the original price.

I hope this helps!