To find the amount of money being discounted from the regular price, multiply the regular price by the decimal conversion of the sale percentage. 20% = 0.2. Multiply 179 by 0.2 to get 35.8. This is the amount of money getting subtracted from the regular price to get the sale price.
179-35.8 = 143.2.
The sale price is $143.20.
Hope that helped you!