Question

a pair of in line skates is on sale for $90 if this price represents a 25% discount, what is the original price

Answer 1

Let:

Op = Original price

Sp = Sale price

Express the discount percentage as a decimal:

25% = 25/100 = 0.25

the original price will be given by:

`\begin{gathered} Sp=Op-0.25Op \\ where\colon \\ Sp=90 \\ solve_{\text{ }}for_{\text{ }}Op\colon \\ 90=Op(1-0.25) \\ so\colon \\ Op=(90)/(1-0.25) \\ Op=120 \end{gathered}`

$120