From CSE Blog
August 27, 2010 at 7:09 am
Source: Asked by Amol
Problem:
An infinite checkerboard is divided by a horizontal line that extends indefinitely. Above the line are empty cells and below the line are an ... (
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From CSE Blog
August 21, 2010 at 7:05 am
Source: CMU Puzzle Toad
Problem: The wizards at Wall Street are up to it again. The Silverbags investment bank has invented the following machine. The machine consists of 6 boxes ... (
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From CSE Blog
August 20, 2010 at 6:46 am
Problem:
A man has two children. He says one of them is a son. What is the probability that the other one is also a son? (Hint: Answer is not 0.5 :P)
I have read this problem ... (
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From CSE Blog
August 18, 2010 at 9:16 am
Source: Saurabh Joshi's Blog
Problem: (copy-pasting from the source)
Suppose we have 13 cards arranged in descending order: K Q J 10 9 8 7 6 5 4 3 2 1
At any move, you can take ... (
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From CSE Blog
August 13, 2010 at 2:14 am
I keep rolling an unbiased die and adding up the sums till it exceeds 100. Once it does, I stop and record that final sum and call it X.
But at the beginning of the game you need ... (
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From CSE Blog
July 28, 2010 at 1:16 am
Source: Tanya Khovanova’s Math Blog
Problem: The Sultan decided to test the wisdom of his wizards. He collected them together and gave them a task. Tomorrow at noon he will ... (
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From CSE Blog
July 25, 2010 at 12:41 am
Source: Australian Mathematical Society Gazette Puzzle Corner
Problem: There are coins of various sizes on a table, with some touching others. As often as you wish, you may choose ... (
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From CSE Blog
July 25, 2010 at 12:40 am
Source: Australian Mathematical Society Gazette Puzzle Corner
Problem: An optimist and a pessimist are examining a sequence of numbers. The optimist remarks, ‘Oh jolly! The ... (
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From CSE Blog
June 26, 2010 at 1:19 am
Let's witness a game. The game involves flipping a coin, which you assume has equal probability of coming up heads or tails. The game is played by two players, A and B, who each ... (
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From CSE Blog
June 20, 2010 at 4:22 am
Source: CMU Spring 2010 Course on Great Theoretical Ideas in Computer Science
Problem: 10% of the surface of a sphere is colored green, and the rest is colored blue. Show that ... (
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From CSE Blog
June 17, 2010 at 10:32 am
Source: 2010 Euler math Olympiad in Russia to Eighth graders. The author of the problem is Alexander Shapovalov
Problem: Among 100 coins exactly 4 are fake. All genuine coins ... (
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From CSE Blog
June 16, 2010 at 1:18 am
Source: Gazette of the Australian Mathematical Society
Problem: A balance scale sits on the teacher’s table, currently tipped to the right. There is a set of weights on the ... (
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From CSE Blog
June 7, 2010 at 9:10 am
My first original question :P
Source of inspiration: Discussion with one of the seniors (CSE, IITB Alumnus 05-09 & Quant Analyst) during Pre-Placement Talk of a firm during ... (
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From CSE Blog
June 3, 2010 at 3:07 am
Source: http://puzzles.nigelcoldwell.co.uk/twentysix.htm
Problem:
A man has built three houses. Nearby there are gas water and electric plants. The man wishes to connect all three ... (
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From CSE Blog
May 29, 2010 at 2:46 pm
Source: CMU Spring 2010 Course on Great Theoretical Ideas in Computer Science Lecture01. Course pointed to me by Aaditya Ramdas (To be CMU Grad Student & CSE-IITB Alumnus)
Problem:
Fit ... (
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From CSE Blog
May 7, 2010 at 8:46 am
Source: Very interesting puzzle from http://forums.xkcd.com/
Problem:
There are 7 people standing in a circle, and each has either a red or a blue hat. The colors of the ... (
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From CSE Blog
April 24, 2010 at 2:38 pm
Source: http://blog.tanyakhovanova.com/
Problem: You have 6 coins weighing 1, 2, 3, 4, 5 and 6 grams that look the same, except for their labels. The number (1, 2, 3, 4, 5, 6) ... (
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From CSE Blog
April 14, 2010 at 2:12 pm
Source: Asked to me by Ankush Agarwal (Sophomore, CSE, IITB)
Problem: There are two kinds of coins, genuine and counterfeit. A genuine coin weighs X grams and a counterfeit ... (
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From CSE Blog
April 2, 2010 at 11:26 am
The paradox imagines that Sleeping Beauty volunteers to undergo the following experiment. On Sunday she is given a drug that sends her to sleep. A fair coin is then tossed just ... (
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From CSE Blog
March 25, 2010 at 8:32 am
Source: http://www.math.utah.edu/~cherk/puzzles.html
Problem: Salt Lake City looks like a rectangle crossed with M streets going from North to South and with N streets going ... (
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From
March 14, 2010 at 3:16 am
Unexpectedly Great Expections Post here shows an awesome paradox. The paradox is called St. Petersburg paradox. I have spent hours explaining this paradox to many smart friends
... (
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From CSE Blog
March 13, 2010 at 2:29 pm
Unexpectedly Great Expections Post here shows an awesome paradox. I have spent hours explaining this paradox to many smart friends of mine. This is probably the best paradox I ... (
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From CSE Blog
March 11, 2010 at 6:26 am
100th Puzzle \m/ \m/
Source: "Fifty Challenging Problems in Probability" by Mosteller F.
Problem: A railroad numbers its locomotives in order 1,2,3.. N. One day you see a ... (
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From CSE Blog
March 9, 2010 at 5:27 am
Source: http://www.ocf.berkeley.edu/~wwu/riddles
Problem:
An enemy submarine is somewhere on the number line (consider only integers for this problem). It is moving at some ... (
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From
March 4, 2010 at 11:56 am
You have N cars that are all traveling the same direction on an infinitely long one-lane highway. Unfortunately, they are all going different speeds, and cannot pass each other.
... (
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