Life | The Universe | Everything | Advanced Search

	New visitors:  Returning members:

This is the Conversation Forum for The Gambler's Fallacy Italian lottery >> Subject: flipping more than one coin Posted Aug 7, 2005 by ender7390   Posting 1 Lets say you have 2 coins. Common sense says that there is a lower chance of both of them coming up heads, but the way you describe it, There is a 50/50... Now I am really confused. There is a 50% chance of the first one coming up heads There is a 50% chance of the second one coming up heads There is a 50% chance they both come up heads? No. Thats not right. There is a 25% chance they both come up heads. There are 2 events, so you need to multiply the probabilities. 1/2*1/2=1/4 So if you flip two coins consecutively, there is a 3/4 chance that the second one will not match the first one. That makes absolutely no sense whatsoever. Could someone straighten me out? I think I'll spend the coins in the slots now. Read the First Reply to this Posting Subject: flipping more than one coin Posted Sep 8, 2005 by adder This is a reply to this Posting   Posting 2 I think i've seen what you've done. As you correctly said the probability of two heads are 1/4 The probability of two tails is also 1/4. 1/4 + 1/4 = 1/2 'there is a 3/4 chance that the second one will not match the first one.' I think you've misssed that matching coins includes tails and tails as well as heads and heads Hope this sorted it out Read the First Reply to this Posting Subject: flipping more than one coin Posted Sep 21, 2005 by ender7390 This is a reply to this Posting   Posting 3 Yes, I get it now. There is actually a 3/4 chance that they won't both be heads you flip any coins, after you flip the first, if it comes up heads, then there is a 1/2 chance. Thanks. Read the First Reply to this Posting Subject: flipping more than one coin Posted Sep 21, 2005 by ender7390 This is a reply to this Posting   Posting 4 Yes, I get it now. There is actually a 3/4 chance that they won't both be heads before you flip any coins, after you flip the first, if it comes up heads, then there is a 1/2 chance. Thanks. (I don't know how to edit a post, I missed a word in my last one) Conversation list Most of the content on h2g2 is created by h2g2's Researchers, who are members of the public. The views expressed are theirs and unless specifically stated are not those of the BBC. The BBC is not responsible for the content of any external sites referenced. In the event that you consider anything on this page to be in breach of the site's House Rules, please click on the relevant button to alert our Moderation Team. Conversation list

Most of the content on h2g2 is created by h2g2's Researchers, who are members of the public. The views expressed are theirs and unless specifically stated are not those of the BBC. The BBC is not responsible for the content of any external sites referenced. In the event that you consider anything on this page to be in breach of the site's House Rules, please click here. For any other comments, please click on the Feedback button above.

About the BBC | Help | Terms of Use | Privacy & Cookies Policy