# Thread: Proportions

1. ## Proportions

Hello,
I do not know how to set-up this proportion in order to solve it:

A radio is on sale for $89. If the sale price is 20% less than the regular price, what is the regular price? Thank you! 2. Originally Posted by VAP Hello, I do not know how to set-up this proportion in order to solve it: A radio is on sale for$89. If the sale price is 20% less than the regular price, what is the regular price?

Thank you!
Let the regular price (which you are solving for) be P. Then the sale price is equal to 80% of P. So the equation you want to solve is: $\displaystyle 0.8P = 89$