To make room for a new inventory of books, Gordon's local bookstore is offering 30% off any book that is over $22.00 and 20% off any book under $20.00. He buys several books with the following prices; $25.00, $18.00, $21.00, $35.00, $12.00 and $10.00. How much will he spend on books? Let's think first. Chain of thought:
He gets 30% off any book over $22 and he buys books that cost $25.00 and $35.00 so the total cost of these books is $25 + $35 = $60.00. At 30% off, the discount on these books is $60 * .30 = $18.00. That mean these 2 books will cost $60 - $18 = $42.00. He gets 20% off any book under $20 and he buys books for $18.00, $12.00 and $10.00 so these books together cost $18 + $12 + $10 = $40.00. at 20% off, the discount on these books is 40 * .20 = $8.00. So these 3 books will cost $40 - $8 = $32.00. He has spent $42.00 on the two most expensive books, $32.00 on the 3 cheapest books, and also bought a book for $21.00, so his total comes to $42 + $32 + $21 = $95.00.
Therefore, the answer is 95.