A local discount store is famous for their motto, "Shop with us and you'll pay 20% less". Their claim is that every item in the
store is already marked down 20% off of retail prices. In this Sunday's ad, they are advertising a scuba mask and snorkel set at their discount price of $28. Use a percent model to determine the original retail price of the scuba mask and snorkel set.
20% off means that the discounted price is equivalent to 80% (100% - 20%) of the retail price.
Calling x the retail price of the scuba mask and snorkel set, then a discounted price of $28 means that this amount of money is 80% of x. Mathematically:
If you want no values of x, it can be any positive value other than 8. If you want all values of x, the value must be 8. If you want only one value of x, it is impossible because both equations have the same slope.
