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Pratik Poddar on Puzzle #195: 1989! Pratik Poddar on Puzzle #197: 10 Friends Vishal Poddar on Puzzle #197: 10 Friends Vishal Poddar on Puzzle #197: 10 Friends Pratik Poddar on Puzzle #196: Bugs on a Bo… Archives
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Tag Archives: logic puzzles
Solution to Puzzle #196: Bugs on a Board
Apologies for not posting anything in the last few weeks, was traveling on work or vacation through this period. This was not a very difficult puzzle, but I got correct answers only from the two people who solve every puzzle … Continue reading
Solution to Puzzle #195: 1989!
I received many correct answers. These included Suman Saraf, Vishal Poddar and Anand Sanghi. Thank you and well done! This puzzle can be solved using the concept of “invariants” and parity. Note that for any numbers a and b (a … Continue reading
Puzzle #196: Bugs on a Board
Yet another very fine puzzle from A Moscow Math Circle: Week by Week Problems by Sergey Dorichenko. Each square of a 9 x 9 board has a bug sitting on it. On a signal, each bug crawls onto one of … Continue reading
Solution to Puzzle #194: Adjacent Cells on a Chessboard
I got only two correct answers for this puzzle – from Suman Saraf and Pratik Poddar – thank you both and well done! I am taking the liberty of copying the answer from Pratik – I find it to be … Continue reading
Puzzle #195: 1989!
This is a beautiful puzzle from Mathematical Circles (Russian Experience) by Dmitri Fomin, Sergey Genkin and Ilia Itenberg. There numbers 1, 2, 3, ….. , 1989 are written on a blackboard. It is permitted to erase any two of them … Continue reading
Puzzle #194: Adjacent Cells On a Chessboard
This is another beauty of a puzzle from A Moscow Math Circle: Week by Week Problems by Sergey Dorichenko. The numbers from 1 to 64 have been placed in each square on a chessboard such that each number appears exactly … Continue reading
Solution to Puzzle #191: 1×4 Rectangular Stone Plates
This was one of my favorite puzzles, though slightly difficult. Unfortunately I got only one correct answer this time, from Suman Saraf. Well done Suman! The answer is “no”. Look at the unusual coloring of the 10×10 board above. Please … Continue reading