Question

Suppose you pay $24 for a pair of shoes that has been discounted 20%. What is the original price of the shoes?

Answer 1

The original price of the shoes was "x", which is the 100% price of the pair of shoes, but you arrived at the store when the 20% sale was going on, so you've got them for 100-20%, which we know is $24, but how much is "x" then?

well      $\bf \begin{array}{ccllll} amount&\%\\ \textendash\textendash\textendash\textendash\textendash\textendash&\textendash\textendash\textendash\textendash\textendash\textendash\\ x&100\\ 24&100-20 \end{array}\implies \cfrac{x}{24}=\cfrac{100}{100-20}$

solve for "x"