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About Author

I am Pratik Poddar, Analyst at Morgan Stanley Strategies and Modeling Division. I completed my B.Tech. from Department of Computer Science and Engineering at IIT Bombay. I am interested in Mathematics and its applications.

One brief random paragraph about my hobbies (in no order) – math-puzzles, word games, mathematics (first love), computer science (second love), coding, poetry, dramatics (third love), debating, electronics, technical activities, watching movies and TV series (fourth love), rubix-cubes, sudoku, collecting coins, economics, cricket, volleyball, table tennis and adventure-sports. I came into this world as a noisy little baby troubling a few nurses and my parents in a small hospital in Patna,Bihar. I did my early education at Patna. Then I came to Jaipur where I appeared for secondary examination. Thereafter, I spent two years at Kota, preparing for IIT-JEE. After securing single digit ranks in IIT-JEE and AIEEE, I came to IIT Bombay. It was an awesome fun and learning experience at IIT. From now, it will be Morgan Stanley (Bombay rocks \m/)

You can find my CV/Resume here

Since last two years, I have been blogging regularly. I like collecting puzzles and discussing them. I maintain a math/cse/puzzle-blog ( which has grown and is now popular in many colleges and many technical companies now. I also maintain a personal blog ( which is mostly random blabbering.

My LinkedIn Profile:

Popular posts from this blog

Asking a girl out

This is not a puzzle. So, for those of you who follow this puzzle blog, please bear with me for just one post. Interesting Math in this article though :P

Most of my friends already read an article that I wrote more than an year back - "Speak Up"

Here, inspired by the movie, The Beautiful Mind, I give a mathematical analysis of asking a girl out. Nice time it is. Feb 10. No plans for Feb 14 and I am sure this article makes me look even more geekier and all the more reason for me to believe that I will be alone, yet again. But what the hell, lets do it!

Note: This is not an independent analysis. There are many "mathematics sites" which does "similar" analysis.

@Consultants, correct me if I am wrong in my estimates. :P

Why is there a need to be selective?

From the age of 15, I guess there are approximately 3,600 girls I have liked (On average days, I don't see new girls. But going outside, I like about 30 girls. Saying that I go out once every week right …

Consecutive Heads

Let's say A keep tossing a fair coin, until he get 2 consecutive heads, define X to be the number of tosses for this process; B keep tossing another fair coin, until he get 3 consecutive heads, define Y to be the number of the tosses for this process.

1) Calculate P{X>Y}
2) What's the expected value of X
3) What's the expected value of Y

This is probably the hardest puzzle I have ever put on my blog. Hence, I will post its solution in the post directly rather than on comment.

(Solved by me finally after 13 months :))

Make a state diagram. Let the state be (a,b) where a is the number of consecutive heads streak "A" is on currently and b is the number of consecutive heads streak "B" is on currently.

So, (0,3) (1,3) are final accepted states and (2,0) (2,1) (2,2) (2,3) are failure states. If you get tails, your contribution to the state reaches to "0"

f(State) = P(X>Y | "State" configuration initially)

f(0,0) = 1/4[f(…

Fraction Brainteaser

Sent to me by Gaurav Sinha

Siddhant writes a Maths test and correctly answers 5 out of 6 Arithmetic questions and 20 out of 28 Geometry questions. In total, Siddhant scores 25 out of 34. 

Vaibhav writes another Maths test and correctly answers 20 out of 25 Arithmetic questions and 6 out of 9 Geometry questions. in total, Vaibhav scores 26 out of 34.

Note that
a) Vaibhav scores more than Siddhant
b) Siddhant score better than Vaibhav in both individual topics - 5/6 > 20/25 and 20/28 > 6/9

How is it possible?