Question

A sofa is on sale for 73% off. The sale price is $172.80. What is the regular price?

Answer 1

To get the answer you have to divide the sale price $172.80 by 73%.
So first you turn 73% into a decimal by moving the decimal two places to the left turning it into .73 

$172.80 divided by .73 = $236.71

You can check by then multiplying $236.71 with .73 

Answer 2

The sale price is 27% so we multiply 172.80 by 3 to get a total of  518.40 which is 81% of the original cost but now how do we find the other 19%? well 172.80 divided by .27 gives us 6.40 all we have to do is do the equation 6.40*19 which is  121.60 now we add 518.40 with 121.60 to get 640.00