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# Riddle watch

1. (Original post by samboosa0)
yh it would but there are no time restrictions and the method still works
OK fair enough.
2. (Original post by anosmianAcrimony)
You are blindfolded and required to sort twenty pennies into two piles with the same distribution of heads and tails in each pile. You know that of the twenty, ten begin heads-up and ten begin tails-up, but you have no means of determining the position of any of the pennies.
whats the solution to this one?
3. (Original post by Xin Xang)
19 times because, the person themselves must have necessarily been chosen in order to have seen the lever in the first place. Any more than 19, and you will be waiting there for ever for the 20th person.
The people are counted by the number of times the counter has seen the counting lever in the up position. What if the counting lever begins in the up position, producing a false positive? Remember, the first inmate to visit the room doesn't know that someone hasn't already been there.
4. (Original post by samboosa0)
whats the solution to this one?
Spoiler:
Show
Divide the pile of twenty pennies into two piles of ten apiece. Because the pennies begin with ten face up and ten face down, you will have in your two randomly selected piles, for example, seven tails up and three heads up in one pile and seven heads up and three tails up in the other. At that point, it becomes obvious that you can make the distribution of heads and tails in each pile the same by flipping all the pennies in one pile over.
5. (Original post by anosmianAcrimony)
Spoiler:
Show
Divide the pile of twenty pennies into two piles of ten apiece. Because the pennies begin with ten face up and ten face down, you will have in your two randomly selected piles, for example, seven tails up and three heads up in one pile and seven heads up and three tails up in the other. At that point, it becomes obvious that you can make the distribution of heads and tails in each pile the same by flipping all the pennies in one pile over.
But for example if 3 are tails up and 7 heads up then when you flip all of them over then the 7 will be tails up and 3 heads up so I don't get it. How does that work?

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6. What is in my pocket?
7. (Original post by KingStannis)
What is in my pocket?
hmm enlighten us..?
8. (Original post by anosmianAcrimony)
The people are counted by the number of times the counter has seen the counting lever in the up position. What if the counting lever begins in the up position, producing a false positive? Remember, the first inmate to visit the room doesn't know that someone hasn't already been there.
Wow!! I hadn't thought of that.

You're right. I'm not sure how to get around that.
9. (Original post by KingStannis)
What is in my pocket?
The preciousssss!
10. Question: Sum Sam and Product Pete are in class when their teacher gives Sam the Sum of two numbers and Pete the product of the same two numbers (these numbers are greater than or equal to 2). They must figure out the two numbers.

Sam: I don't know what the numbers are Pete.
Pete: I knew you didn't know the numbers... But neither do I.
Sam: In that case, I do know the numbers.

What are the numbers?
11. (Original post by IAmEllie)
Question: Sum Sam and Product Pete are in class when their teacher gives Sam the Sum of two numbers and Pete the product of the same two numbers (these numbers are greater than or equal to 2). They must figure out the two numbers.

Sam: I don't know what the numbers are Pete.
Pete: I knew you didn't know the numbers... But neither do I.
Sam: In that case, I do know the numbers.

What are the numbers?
3&4?
12. (Original post by anosmianAcrimony)
You are blindfolded and required to sort twenty pennies into two piles with the same distribution of heads and tails in each pile. You know that of the twenty, ten begin heads-up and ten begin tails-up, but you have no means of determining the position of any of the pennies.
Couldn't you just feel each of the pennies? You wouldn't be able to know if it's heads or tails, but the similar feeling between the coins should allow you to sort them into piles which would then be heads and tails?
13. You have one of me and I’m easy to touch,
I’m hard to look at, but you can in a clutch.Yet you’re told to watch me, or get your friends’.
I’m often referred to when you make amends.You can throw me out but not away,
I cause many pain, every day.What am I?
14. (Original post by Jiaaaaaa)
You have one of me and I’m easy to touch,
I’m hard to look at, but you can in a clutch.Yet you’re told to watch me, or get your friends’.
I’m often referred to when you make amends.You can throw me out but not away,
I cause many pain, every day.What am I?
This may sound stupid but is it back?
15. (Original post by TheHonestMisty)
This may sound stupid but is it back?
16. (Original post by Jiaaaaaa)
The one who makes it sells it.
The one who buys it doesn't use it.
The one who's using it doesn't know he's using it.
What is it?
17. (Original post by TheHonestMisty)
The one who makes it sells it.
The one who buys it doesn't use it.
The one who's using it doesn't know he's using it.
What is it?
Poison?
18. (Original post by Xin Xang)
Poison?
Nope
19. (Original post by TheHonestMisty)
The one who makes it sells it.
The one who buys it doesn't use it.
The one who's using it doesn't know he's using it.
What is it?
drugs?
20. (Original post by samboosa0)
drugs?
No

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