{"product_id":"puzzle-box-volume-1-peter-grabarchuk-9780486810041","title":"Puzzle Box, Volume 1","description":"\u003ci\u003eMultiplying my age by 6 then subtracting 6 produces the same result as subtracting 7 from my age then multiplying by 7. How old am I?\u003cbr\u003eOn my broken calculator with keys ] -   x =, the only functional number is 7. How can I get 34 to appear in the readout?\u003cbr\u003eA country mints four denominations of coins, in whole numbers of cents. It takes four of these coins to make 21 , or 24 , or 25 , or 26 . What are the denominations of the coins?\u003cbr\u003e\u003c\/i\u003eThese and almost 300 other mathematical puzzles appear in this original collection, devised by world-renowned mathematicians, puzzle creators, and devoted puzzle lovers. A unique puzzle project, it unites the efforts of a dozen authors, including software engineer Andrea Gilbert and Bram Cohen, author of the P2P BitTorrent protocol. \u003cbr\u003eSeventeen different types of challenges include 3-D puzzles, chess puzzles, connections, dissections, foldings, geometrical puzzles, logic problems, matchstick puzzles, mazes, moving pieces, number puzzles, put-togethers, strimko, sudoku, visual puzzles, weightings, and word puzzles. The difficulty level of each puzzle is marked by stars, ranging from 2 to 5. Average difficulty level is about 3 stars, promising puzzle enthusiasts many entrancing hours of solving and enjoyment.\u003cbr\u003e\u003cbr\u003e\u003cb\u003eAuthor:\u003c\/b\u003e Peter Grabarchuk\u003cbr\u003e\u003cb\u003eISBN-10:\u003c\/b\u003e 0486810046\u003cbr\u003e\u003cb\u003eISBN-13:\u003c\/b\u003e 9780486810041\u003cbr\u003e\u003cb\u003ePublisher:\u003c\/b\u003e Dover Publications\u003cbr\u003e\u003cb\u003eLanguage:\u003c\/b\u003e English\u003cbr\u003e\u003cb\u003ePublished:\u003c\/b\u003e 11\/16\/2016\u003cbr\u003e\u003cb\u003ePages:\u003c\/b\u003e 96\u003cbr\u003e\u003cb\u003eFormat:\u003c\/b\u003e Paperback\u003cbr\u003e\u003cb\u003eWeight:\u003c\/b\u003e 0.60lbs\u003cbr\u003e\u003cb\u003eSize:\u003c\/b\u003e 10.90h x 8.20w x 0.20d","brand":"Peter Grabarchuk","offers":[{"title":"Paperback","offer_id":44047459123455,"sku":"9780486810041","price":16.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0662\/2982\/9887\/files\/img_63cbb2f9-8f10-4665-ae1e-25db8395c4e6.jpg?v=1684990333","url":"https:\/\/www.whiterainbookhouse.com\/products\/puzzle-box-volume-1-peter-grabarchuk-9780486810041","provider":"WR Book House","version":"1.0","type":"link"}