Dookie_-_Monster

Dookie_-_Monster t1_j6nole0 wrote

The chance of picking one paper out of a stack is 1 / n (n is the number of papers).

The chance a piece of paper goes in the trash is 1/(.5n). The chance that piece is then picked out of the trash is then 1/(.5n) again. Multiply those and you get 1/(.25n^2).

So we can compare them to see if those are actually the same quantity.

1 / n < 1/(.25n^2)

n < .25n^2

4n < n^2

4 < n or n > 4

So if your stack has 4 or more pieces of paper in it, getting the paper out of the garbage is less likely (i.e. luckier) than just picking the paper out of the whole stack.

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