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# bonanova

Member Since --
Offline Last Active Yesterday, 07:46 AM

### #342037Walking on a lattice

Posted by on 08 April 2015 - 10:51 AM

Spoiler for

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### #341995Sliding swing

Posted by on 28 March 2015 - 12:47 PM

A little more fun:

Let the lower mass be a fraction
f of the upper mass.
What are the values of
f for which the upper ball should be pulled distances of
[a] 0.5 and [b] 1.0 from the hook in order for the balls to collide?

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### #341935Horizontally randomly moving particle

Posted by on 15 March 2015 - 06:04 AM

Spoiler for For two paths, A is crossed twice

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### #341933Horizontally randomly moving particle

Posted by on 14 March 2015 - 10:21 AM

Spoiler for

Agree.

Spoiler for

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### #341777Checkerboard Challenge

Posted by on 02 March 2015 - 08:51 PM

Spoiler for Takes only four

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### #341748A point in an equilateral triangle

Posted by on 28 February 2015 - 05:55 AM

Spoiler for

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### #341698Squared rays

Posted by 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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### #341686A simple integer function

Posted by on 24 February 2015 - 11:55 AM

Spoiler for Solution

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### #341685A simple integer function

Posted by on 24 February 2015 - 11:37 AM

Great job.

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### #341593The Price of Wine

Posted by on 16 February 2015 - 07:12 AM

Much more satisfying, as well! Good one.

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### #341581The Price of Wine

Posted by on 15 February 2015 - 06:21 AM

Spoiler for

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### #341521k-man's kasino

Posted by 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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### #341493The Knives and bottles table

Posted by on 03 February 2015 - 02:30 PM

Spoiler for ok

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### #341479Polygons make a line

Posted by 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.

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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### #341390The n-gon eats out

Posted by 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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