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3 replies to this topic

### #1 Aatif

Aatif

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Posted 15 February 2008 - 08:31 AM

How many cylindrical pencils (1 cm radius, 10 cm length) can you arrange, so that each of them touches the other?

If the pencils were infinite in length, will the solution change?
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### #2 rookie1ja

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Posted 15 February 2008 - 01:05 PM

7 pencils ... check puzzle named Touch

I guess infinite length would decrease the number to 6

I am quite curious about photos documenting higher numbers
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Posted 15 February 2008 - 02:24 PM

what if they were different lengths?
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### #4 Aatif

Aatif

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Posted 16 February 2008 - 06:48 PM

I don't believe 7 is the lucky number though i have seen the pics too ..
whats the mathematical logic behind it?

and how does it change t 6 for infinitely long pencils?
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