Category Archives: Puzzles

Puzzle #170: Rectangle and the Oil Well

This is a wonderful puzzle that I saw today after a long time. I was asked this puzzle in an interview in Microsoft back in 1994 March – yes it has been a long time! I saw it today in … Continue reading

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Puzzle #168: Who Gets the Easter Eggs?

This is a delightful and a very counterintuitive puzzle, again from the NSA collection. Original puzzle has been written by Tim C., an Applied Research Mathematician at NSA. Alice has a dozen cartons, arranged in a 3×4 grid, which for … Continue reading

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Puzzle #167: 4 Rats in a Star

Yet another wonderful puzzle from the NSA collection. Please do have your children try this one! RATS x 4 = STAR Each instance of a letter stands for the same digit, no two letters represent the same digit, and R … Continue reading

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Puzzle #166: Donut Sharing

This puzzle is a variation of a puzzle I had posted very early (amongst my first 10 posts). It is very simple, and intended for children. Thanks to Suman Saraf for contributing this one. Alice and Bob go into their … Continue reading

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Puzzle #165: Truth & Lies – 7 of them!

Welcome back, and a very happy new year to all of you. Lets start with a new puzzle before I post solutions to previous problems. I will begin this week with a very nice puzzle from the NSA collection. Here … Continue reading

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Puzzle $164: The Physics Puzzle

Here is the second one for today, and something to keep you all occupied in the holidays, even though I know you all will have better things to do like beach, snow, …. This one is contributed by Suman Saraf, … Continue reading

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Puzzle #163: The “Hatke” Puzzle

Friends, I am going to be traveling/ on vacation over the next few weekends and hence taking the liberty of posting two puzzles this weekend, and restart in the weekend of Jan 6th. This one is a very “hatke” (in … Continue reading

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Puzzle #162: Who finished 2nd in 100m?

Very nice puzzle from the NSA collection. We have seen versions of this in the past, I loved this one as well. Three athletes (and only three athletes) participate in a series of track and field events. Points are awarded … Continue reading

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Puzzle #161: Lost Car Key Puzzle

This is a very nice probability puzzle, variations of which we have done in the past. This one is contributed by Suman Saraf – Thanks Suman! I drive to work, and put my car keys in my pocket. Whenever I … Continue reading

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Puzzle #160: $50 for All

This is yet another beautiful puzzle from the NSA collection! At a work picnic, Todd announces a challenge to his coworkers. Bruce and Ava are selected to play first. Todd places $100 on a table and explains the game. Bruce … Continue reading

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