A customer at a clothing store is buying a pair of pants and a shirt. The store is having a 15​%-off sale on all pants. The customer has a coupon for 10​% off her entire purchase. The coupon cannot be combined with any other​ offers, so she can choose only one option. Let n represent the original price of the pants and s represent the price of the shirt. Write two equivalent expressions for each option. If the original cost of the pants is ​$25 and the shirt is ​$20​, which option should the customer​ choose?