Two Coins: Probability

[DeletedUser9470]

-Neo- wins!

what did i win?

 

[DeletedUser28839]

I earlier thought the answer is 33%, but now i favor 50%

i toss 2 coins,
i can get the following results
HT
TH
TT
HH

now someone goes and tells me one is heads.
even though we don't know which one is heads, we are only left with two options :

the second coin is either tails or heads.so the probabliltiy will be 50%.In this case you don't need to know which one is heads, you need to know one is heads, that has already been declared so you don't investigate on that coin.Your question is based on second coin only!

 

[nashy19]

I earlier thought the answer is 33%, but now i favor 50%

i toss 2 coins,
i can get the following results
HT
TH
TT
HH

now someone goes and tells me one is heads.
even though we don't know which one is heads, we are only left with two options :

the second coin is either tails or heads.so the probabliltiy will be 50%.In this case you don't need to know which one is heads, you need to know one is heads, that has already been declared so you don't investigate on that coin.Your question is based on second coin only!

The TT result is not possible if someone tells you truthfully that one coin is heads. The TT flips are either ignored or they become TH/HT flips, it says "has" and that's vague.

If they are ignored you get 33%.
If the heads is simply guaranteed then you get 25% HH and 37.5% for both TH/HT.

Your second coin could be treated as the first, heads can appear anywhere but if you flip it by luck then it's not handed to you just to fulfill the requirement.

You could use the test results a few pages back and interrupt them in different ways.

 

[DeletedUser]

I earlier thought the answer is 33%, but now i favor 50%

i toss 2 coins,
i can get the following results
HT
TH
TT
HH

now someone goes and tells me one is heads.
even though we don't know which one is heads, we are only left with two options :

the second coin is either tails or heads.so the probabliltiy will be 50%.In this case you don't need to know which one is heads, you need to know one is heads, that has already been declared so you don't investigate on that coin.Your question is based on second coin only!

Groundhog day. Explaining this is like reinventing the wheel.

Think of this: if someone told you the first coin just came up heads and asked you for the chances of a double-heads coming up, you would rightly say 50%.
But if (as here) you are only told that at least ONE of the coins is heads (it may be the first or it may be the second), c 'est different n'est-ce pas????

Voyez????