Number of Nails in Picture?

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How many nails are in the picture? How did you arrive at this solution?

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phinds
Gold Member
2019 Award
How many nails are in the picture?
lots

How did you arrive at this solution?
I guessed

Excellent guess. :)

amount of nails < infinity

mfb
Mentor
Including expected, but not visible nails, between 1 000 and 100 000.
The remaining uncertainty can be reduced by a [insert your favorite useless education here] student, ...
...weighting them (and a few individual nails). You don't want to wait until he counted them, right?

D H
Staff Emeritus
How many nails are in the picture?
800-900.
How did you arrive at this solution?
That looks like about 5 pounds of 2" common nails, so 800-900 nails, depending on the manufacturer.

best bet is 1600. Please count it!

D H
Staff Emeritus
Don't you just hate these post and run kind of brain teasers?

It's been two weeks since the person who posted the question last came back to the site.

I DON'T KNOW. However I will try a stupid approximation technique:

Let N be the number of nails ,
V be the average volume of the nail bulk, and u be the average volume of a single nail (at different orientations). Let l be the length of a single nail. Exclude the empty spaces between the nails!

Identify the average shape of the nail bulk. Find u with respect to l (I.e. u = f(l) ). Find V with respect to l (I.e. V = g(l) ).

Now Nu = V, so N = (V/u) = g(l)/f(l)