Use the Tootsie Roll Pop Owl Method.

"Due to the laws of probablity it could be an infinite number of times before you grab the last pistachio"

Someone came upon my computer and typed that.

Do you need to grab 10 pistachios on the last grab?

This post has been edited by DustyHaru: Mar 2 2010, 03:02 AM

You have no way of dictating how many shelled and unshelled pistachios you grab, except for on the very first grab. Therefore, it could be any number of times. I'm certain there's a finite point, but I don't care enough to actually work out the math.

42.

If there are less than ten, you grab that many.

It's been a while since I thought about this problem, but I don't think you can go on indefinitely.

Somewhere between 12 and 21 grabs. :V

You need at least 20 grabs, since you pick up each pistachios twice (once to shell it and drop it, once to eat it).
It's at most 21 if an odd number persists.

I just can't figure out how to explain it in a math way to be math.

I feel rather silly now. I diagrammed it wrong :V. lol that'll teach me to attempt mathematics puzzles at 2 AM.

who fucking cares? the important thing is eating them right?

Isn't there an equation for this? I'll see if I can figure it out.

First scoop, there is a 100% chance of getting 10 unshelled. Second scoop there's a 1900/99% chance of getting a pistachio for each pistachio out of ten. Hmm.

Also:



Yes, there is. There is a finite amount of pistachios in the bowl. That means there is a finite amount of scoops to get them all out if eat at least one. With each scoop afterwards up to a finite point, you are eating either 0 or 10, and you are either unshelling 0 or 10, which add up to the unshelled number.

I would say 20 just by looking at it, but maybe thats the "trick". If one were to luckily get all shelled first, then unshelled, with 10 in hand, it would take 10 turns both times. And if one were to always repick the same unshelled pistachios (as in failure to acquire new shelled pistachios every other pick), it would also end up to be 20 as you would take one scoop to unshell, and one scoop to eat. Which would be the opposite results of each other. This should hold up to multiple bowls, by the way. As in, if you were to split the bowls into ten bowls, it would still take 20, since each bowl you would take all of them and unshell all of them, since pulling them apart and putting them together equals the same thing (For example, 296x90 = (200+90+6)(90) (26640 = 18000+8100+540) (or (100)=(10)(10)).

If that isn't the answer, why don't you post it later so I learn something. I've always been the person who was rusty on the basics but knowedgeable on complex shit. Thats generally how math majors should take the field anyways. Thats why most public school books have the answers in the back. Its so if you get the wrong answer, you can recheck your work to see where you slipped up. Use it all the time.

This post has been edited by Elnendil: May 1 2010, 03:55 AM

Every time I come back to this topic, I think, "Wait, people are still posting solutions? I thought the answer was given already..."

Shio: http://www.youtube.com/watch?v=Y2ap3CJM9jQ
You lose points.

And reading the topic again, I confirmed the answer in post #10. I don't know why people are still posting.

math is not meant for me, bring something easier. im not smart you know :(

We don't read.

Looks like I was wrong either way.

You just missed the in-between case. In a case-by-case proof, you have to make sure to get all cases.

I'll keep that in mind.