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Online Last Active Today, 07:40 PM

#341777 Checkerboard Challenge

Posted by bonanova on 02 March 2015 - 08:51 PM

Spoiler for Takes only four

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#341748 A point in an equilateral triangle

Posted by bonanova on 28 February 2015 - 05:55 AM

Spoiler for

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#341698 Squared rays

Posted by bonanova on 26 February 2015 - 01:55 AM

Yeah, I had to think that point through for a moment.

I saw it as having a sum that I didn't know how to evaluate.

So I added and subtracted the term that would make the sum zero.

That step simultaneously evaluated the sum and added 2 to the mix.


Your approach is neater, reasoning that the answer is not changed if you add the squared length of the nth ray.


That's a nice insight.

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#341686 A simple integer function

Posted by bonanova on 24 February 2015 - 11:55 AM

Spoiler for Solution

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#341685 A simple integer function

Posted by bonanova on 24 February 2015 - 11:37 AM

Great job.bona_goldstar.gif


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#341593 The Price of Wine

Posted by bonanova on 16 February 2015 - 07:12 AM

Much more satisfying, as well! Good one.

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#341581 The Price of Wine

Posted by bonanova on 15 February 2015 - 06:21 AM

Spoiler for

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#341521 k-man's kasino

Posted by bonanova on 09 February 2015 - 09:25 PM

To celebrate the Grand Opening of his new casino, k-man offered the first 1000 patrons the opportunity to win some pocket change by playing a game that carried the catchy phrase Flip while you're a-Head. Each patron paid $100 to flip a coin multiple times, winning $100 for every H (heads) that appeared, and stopping (without penalty) at the first appearnace of a T (tails.)

What was k-man's expected cost for this gesture of good will?


A coveted bonanova gold star for an answer from the The Book.

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#341493 The Knives and bottles table

Posted by bonanova on 03 February 2015 - 02:30 PM

Spoiler for ok

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#341479 Polygons make a line

Posted by bonanova on 31 January 2015 - 01:44 AM

@Perhaps check it again


I thought of that distinction as well, and it led me back to the OP, where I found that the word "interior" is not mentioned.

It has been agreed that a line cannot always pass through the interior of polygons so described.

It has been clarified that BMAD asks something different.


Not all Denizens share English as their primary language, so discussions like this one are generally helpful if taken in that regard.

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#341390 The n-gon eats out

Posted by bonanova on 15 January 2015 - 12:50 PM

n people party at a restaurant, sitting at the vertices of an n-gon-shaped dinner table. Their orders have been mixed up -- in fact, none of them have received the correct entree. Show that the table may be rotated so that at least two people are sitting in front of the correct entree.

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#341346 I'm not a skier

Posted by bonanova on 01 January 2015 - 04:52 AM

Spoiler for Last guess of 2014

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#341345 Empty a peg and marry a Princess (difficult)

Posted by bonanova on 01 January 2015 - 04:20 AM

I believe plasmid's line of analysis will lead to a solution.


To achieve a degree of closure this year, here is the 2nd of the two proofs referenced in post 7.

It is much simpler than it first appears. Working an example is the best way to understand it.


Spoiler for

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#341238 Pawn Alice

Posted by bonanova on 07 December 2014 - 04:31 PM

Spoiler for no more than

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#341032 Upside Down Cake

Posted by bonanova on 12 November 2014 - 12:22 PM

Spoiler for Demonstration for irrational case

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