#### Answer

The original price of the dress was 175 dollars.

#### Work Step by Step

Let s represent the original price.
We can use the following guideline to solve this problem.
Original selling price - Discount = Discount sale price
s - 20% $\times$ s = 140
s - 0.2s = 140
0.8s = 140
Divide both sides by 0.8:
s = 175
The original price of the dress was 175 dollars.