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Q: Probability ( Answered,   1 Comment ) Question
 Subject: Probability Category: Science > Math Asked by: johnjri1-ga List Price: \$2.00 Posted: 24 Nov 2006 19:00 PST Expires: 24 Dec 2006 19:00 PST Question ID: 785371
 ```Event 'A' has a 50% chance of ocurring. The only way event 'B' can occur is if event 'A' occurs; If event 'A' occurs, event 'B' has a 50% chance of occuring. The only way event 'C' can occur is if event 'B' occurs; If event 'B' occurs, event 'C' has a 50% chance of occuring. What are the chances of event 'C' occuring? I think it is 50% x 50% x 50% = 12.5%, but I am not sure that is right. Please show your math if I am wrong.``` ```Let's say the action you're talking about is a flip of the coin, and the "event" would be the coin coming up Heads. For the first flip, you have a %100 chance of getting to flip, and 50% chance it comes up heads. There's then a 50% chance of a second flip, and a 50% chance of that being Heads -- .50 * .50 = 25%. So...there's a 25% chance of getting to a third flip, which has a 50/50 chance of Heads -- .25 * .50 = 12.5% As you thought, the odds are 12.5%. Cheers,, pafalafa-ga``` Clarification of Answer by pafalafa-ga on 28 Dec 2006 10:22 PST ```It dawned on me this might be some math homework for school, and that you might like some extra help. If so, just let me know by posting a note, here, and I'll provide whatever math homework help I can. Probability is always a fascinating, but challenging topic. Cheers, Dave``` ```P(A)=0.5 P(B/A)=0.5 P(C/A?B) = 0.5 Therefore, P(C) = P(A?B?C) = P(A)* P(B/A)* P(C/A?B) = 0.5*0.5*0.5 P(C) = 0.125 = 12.5%``` 