{"product_id":"puzzle-box-1-andrea-gilbert","title":"Puzzle Box. Volume 1","description":"Multiplying 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?On my broken calculator with keys + - ÷ x = the only functional number is 7. How can I get 34 to appear in the readout?A 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?These 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. Seventeen 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.\t\u003cp\u003e\u003cb\u003eAge Range:\u003c\/b\u003e 10 and up \u003cbr\u003e\u003c\/p\u003e\u003cp\u003e\u003cb\u003ePaperback:\u003c\/b\u003e 96 pages\u003c\/p\u003e\u003cp\u003e\u003cb\u003ePublisher:\u003c\/b\u003e Dover Publications; Act Csm edition (November 16 2016)\u003c\/p\u003e\u003cp\u003e\u003cb\u003eLanguage:\u003c\/b\u003e English\u003c\/p\u003e\u003cp\u003e\u003cb\u003eISBN-10:\u003c\/b\u003e 0486810046\u003c\/p\u003e\u003cp\u003e\u003cb\u003eISBN-13:\u003c\/b\u003e 978-0486810041\u003c\/p\u003e                                                                                    \u003cp\u003e\u003cb\u003e    Product Dimensions:     \u003c\/b\u003e    8 x 0.2 x 11.5 inches    \u003c\/p\u003e\u003cp\u003e\u003cb\u003eShipping Weight:\u003c\/b\u003e 10.4 ounces \u003c\/p\u003e    \u003cp\u003e\u003cb\u003e\u003c\/b\u003e\u003c\/p\u003e","brand":"Activities. Crafts \u0026 Games","offers":[{"title":"Paperback","offer_id":30934503784551,"sku":"486810046","price":25.6,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0265\/5879\/1783\/products\/61Ev8fkInFL.jpg?v=1571710423","url":"https:\/\/dreams5s.myshopify.com\/products\/puzzle-box-1-andrea-gilbert","provider":"Dreams5s","version":"1.0","type":"link"}