Folding paper in 1/2 13 times.

[Beezil]

you must realize how many thicknesses of paper you would have in a "fold up" after each fold-in-half.

it is NOT a geometry trick. It is basic math.

not talking about how wide, long or thick the paper is, BEFORE you fold the paper, you have ONE thickness.

fold it in haf ONCE leaves you with TWO thicknesses of paper. do it again and you have FOUR.

this can be expressed like this:

(number of folds)---(number of thicknesses)

0---1
1---2
2---4
3---8
4---16
5---32
6---64
7---128
8---256
9---512
10---1024
11---2048
12---4096
13---8192

if you have 8192 thicknesses of .003" paper, the fold-up will be 24.576" high.

therefore, you need a starting length 24.576" to the 13th power (theoretical minum) in order to physically fold the paper.

its that simple.

the relationship between the paper thickness and the starting length is proportional.

 

[Beezil]

Actually, it will bulk-up more than the calculable sum. Paper folded in half without allowing the air to escape would include the trapped air.

the mathematical problem assumes the best theoretical possibility, and actually air does not add as much of a challenege to the real-world solution as does the problem with what kind of increasing radii of each fold location and the lenth needed to wrap around the previous fold, which I haven't even gone into without having to figure that part of it out.

I doubt you'd be able to squeeze much free air from between the pages of a phone book.

 

[bchulett]

the mathematical problem assumes the best theoretical possibility, and actually air does not add as much of a challenege to the real-world solution as does the problem with what kind of increasing radii of each fold location and the lenth needed to wrap around the previous fold, which I haven't even gone into without having to figure that part of it out.

I understand the real world scenarios....

I'm in the printing business.

Plus he said "piece of paper" ... not roll of paper.

Riddle is misleading ...

 

[Beezil]

yeah, even though the problem is not intended to be a "riddle" per se, when one says "piece" of paper, one does assume the proportions and size of an 8 1/2" x 11" PIECE of paper.

an 8000 foot long roll of newsprint is STILL a piece of paper!

damn mathmatical dicks.

 

[bchulett]

yeah, even though the problem is not intended to be a "riddle" per se, when one says "piece" of paper, one does assume the proportions and size of an 8 1/2" x 11" PIECE of paper.

an 8000 foot long roll of newsprint is STILL a piece of paper!

damn mathmatical dicks.

Well sorta ... only after it's converted.

 

[bchulett]

I doubt you'd be able to squeeze much free air from between the pages of a phone book.

BTW ....

Phone books are "Perfect Bound":

Printed "roll stock" converts to folded signatures and are gathered and clamped. Folded side of the leaf is ground and glued as single sheets ... the cover is wrapped and bonds to the backbone ... and then receives a final 3-way trim. The air escapes and lays flat.

That's a snapshot of telephone book process.

 

[yuppiexj]

DAMN, I thought I was the epitome of anal retentive geekiness.
I have been relieved of the crown.

 

[seanR]

BTW ....

Phone books are "Perfect Bound":

Printed "roll stock" converts to folded signatures and are gathered and clamped. Folded side of the leaf is ground and glued as single sheets ... the cover is wrapped and bonds to the backbone ... and then receives a final 3-way trim. The air escapes and lays flat.

That's a snapshot of telephone book process.

I just carry the Durand phone book around on a 3 x 5 in my shirt pocket.

 

[bchulett]

I just carry the Durand phone book around on a 3 x 5 in my shirt pocket.

I just call 411 connect.

 

[Grizzley]

Beezil, you're my hero! HAHAHA Actually, this "riddle" if you will, was originally worded that the paper was folded in half each time in opposite directions. Top to bottom, left to right, top to bottom, etc., etc. Family print shop, Grandfather's sick joke on an 8 year old, need I say more. Even tried 23 x 35 onion skin and tissue paper, which was available way back then, and it still didn't work. 40 years in the printing industry and it was always a good joke to pull on the button pushers that the schools put out now for pressmen.

 

[Beezil]

actually, the number of thicknesses is the same even if you fold perpendicularly.

 

[bchulett]

If you cut the paper in half, you can fold it 14 times.

Actually, this is the correct answer.


One "piece" of 11x17 partially cut in half along the 11" length to 10.312".

Fold each attached half as follows:

4 parallel folds ...
Right angle folded three times (3 parallels).

total = 7

Do this to both sides and you've got 14 folds.

Trickery.