Puzzle Box. Volume 1

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.

Age Range: 10 and up

Paperback: 96 pages

Publisher: Dover Publications; Act Csm edition (November 16 2016)

Language: English

ISBN-10: 0486810046

ISBN-13: 978-0486810041

Product Dimensions: 8 x 0.2 x 11.5 inches

Shipping Weight: 10.4 ounces