A bookstore has a complicated, but nice discount policy. If you buy a $20 book today, you get a 2% discount on your next purchase. Buy a $15 book, and you get 1.5% discount on your next purchase.
If you buy three books that cost $10, $20 and $30, you could buy the $30 book today, the $10 book tomorrow (with a 3% discount) and the $20 book the next day and get a 1% discount. Or you could buy the $30 and $20 book today and get 5% back on your $10 purchase tomorrow.
What is the cheapest way to buy five books at $10, $20, $30, $40 and $50?
* I buy $20 and $30 books today.
ReplyDelete* Then I buy $40 and $50 books in
the next purchase.
* I get 2% discount on this
purchase.so I pay $88.2(90*2/100)
* Next day i buy $10 book on which
I get 5% discount. so I pay $9.5
* Total amount paid is $147.7
I believe you can save more.
ReplyDeleteYou put together $80 worth of books the first day and get 8% on a $70 purchase tomorrow. Or, you could put together $70 the first day and get 7% on a $80 purchase tomorrow. Both ways save you $5.60. Which means you pay a total of $144.40.