Often to the store to buy things you will see, various discounts and discount stores are commonly used to attract customers,


For example, a store USES the "coupon" discount, $100 per purchase of goods, the shop giving $50 gift certificates ", the part of less than 100 yuan to omit any (for example, to buy $888 worth of goods can be entitled to a $400 gift certificates), the use of the gift certificate is: $100 per purchase of goods, can use the store $50 gift certificate as a pay 50 yuan, less than 100 yuan of omit no (such as you have enough gift certificates, then 250 yuan may be used to purchase 560 yuan goods gift certificates, the remaining 560-250=310 yuan to pay in cash, note because you paid 310 yuan in cash, shop to give you $150 gift certificates),


According to this way, customers can obtain many preferential (the equivalent of a few fold)? Media said the equivalent of about fifty percent discount, if middle school maths well, can derive the total discount up to close to (but less than)? To fully understand the problem, need to use a little calculus,

CodePudding user response:

How does this use calculus knowledge