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Tuesday number Two

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Tuesday number Two

#1

Tuesday number Two

Bill Earl

Here's another one to ponder:

You have a container of nails.

If you divide it evenly into 2 piles, you will have one left over.

If you divide it evenly into 3 piles, you will have one left over.

If you divide it evenly into 4 piles, you will have one left over.

If you divide it evenly into 5 piles, you will have one left over.

If you divide it evenly into 6 piles, you will have one left over.

If you divide it evenly into 7 piles, you will have one left over.

If you divide it evenly into 8 piles, you will have one left over.

If you divide it evenly into 9 piles, you will have one left over.

If you divide it evenly into 10 piles, you will have one left over.

If you divide it evenly into 11 piles, you will have none left over.

How many nails are there?

Re: Tuesday number Two

#2

Re: Tuesday number Two --  corrected (maybe)

Alex Y

One nail. All of the piles that it is divided into are empty.

Or assuming you wanted a nontrivial answer:

One more than ten gross score, less M and fourscore.

Unless I messed up the obfuscation ;)

Re: Tuesday number Two

#3

Re: Tuesday number Two

Larry Barrett

I haven't decoded Alex's answer yet, but I think this is a different answer:

One more than a movie title!

Re: Tuesday number Two

#4

Re: Tuesday number Two

Bill Earl

Your trivial answer doesn't work because 1 is not divisible by 11. (read the last line carefully)

If you divide it evenly into 11 piles, you will have none left over.

I may not understand your obfuscation, but the way I caclulate that doesn't work either.

Re: Tuesday number Two

#5

Don't think so

Bill Earl

It may be a film I have never heard of, but a search of IMDB for that name (number) turned up empty.

Re: Tuesday number Two

#6

Re: Tuesday number Two

Alex Y

I messed up my obfuscation; hopefully fixed now. But I don't know of a movie title that fits with my answer.

Re: Tuesday number Two

#7

Re: Tuesday number Two

Alex Y

(read the last line carefully)

Oh, I NEVER do that! :(

If you divide it evenly into 11 piles, you will have none left over.

Whoops!

Re: Tuesday number Two

#8

Re: Tuesday number Two

Dan Donaldson

vente cinco mil dos cientos y uno

Re: Tuesday number Two

#9

s� se�or   


Re: Tuesday number Two

#10

Re: s� se�or 

Larry Barrett

Dan's answer much simpler, but my answer also works, I think:

10! +1.

Re: Tuesday number Two

#11

10! is way too big 


Re: Tuesday number Two

#12

Tuesday Answer

Bill Earl

Dan was the first with a recognizably correct answer: 25,201

I'm not sure if I'm decoding it right, but I think Alex's revised answer works out to be too high.

Re: Tuesday number Two

#13

But he didn't ask for the smallest solution

Alex Y

I agree with your solution (once Bill pointed out that I should read more carefully!).

My problem with Larry's is not the size, but how to know that 10!+1 is a multiple of 11. It may be, but I don't see how to tell that.

Re: Tuesday number Two

#14

Re: Tuesday Answer

Alex Y

I'm not sure if I'm decoding it right, but I think Alex's revised answer works out to be too high.

Correct, and it was = 1 mod 11, because of my misreading of the problem. The correction was to my obfuscation, not to the answer. I got Don's answer, but after he did.

My attempted obfuscation was

One more than ten gross score, less M and fourscore

1+ 10 * 144 * 20 - 1000 - 4 * 20 = 27,721, which is the smallest number greater than 1, which is equal to 1 mod 2,3,4,...,and 11, the problem I read, even if it's not the one you posted

Good problem!

Re: Tuesday number Two

#15

Re: But he didn't ask for the smallest solution

Larry Barrett

I stumbled onto my solution (10! + 1) by the straightforward way of finding a number that would satisfy the first 9 criteria (remainder of 1), and then discovered that it was also divisible by 11. My handy dandy pocket calculator has a ! key, so was easy to compute 10! = 3628800, so 10! + 1 = 3628801.

328801/11 = 329891. I have not discovered a simple way to know that 10! +1 is divisible by 11 without doing the division.

So not a very elegant solution, but it is a solution.

Re: Tuesday number Two

#16

Actually

Dan Donaldson

More elegant than the way I did it.

Re: Tuesday number Two

#17

How to tell if a number is evenly divisible by 11

Larry Barrett

Pondering how to know without doing the division, I Googled "rule for dividing by 11" and found an interesting web site that has simple rules for knowing if a number is evenly divisible by 2, 3, 4, 5, 6, 8, 9, 10, and 11.

Here is the rule for 11:

A number passes the test for 11 if the difference of the sums of alternating digits is divisible by 11.

So for 10!+1 = 3628801 the sum of alternating digits is (3+2+8+1)= 14 and (6+8+0)=14. Difference is 0; 0 is evenly divided by 11, so 10!+1 is, too.

Amazing what you can find on the web.

👍 This page answered my questions

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