# Expected value of a not-fair coin

• Jun 21st 2011, 02:14 AM
mosquetero
Expected value of a not-fair coin
Hi!

I have a not-fair coin and the expected value to get a "head" is 10 tosses. The question is: What is the probability of getting heads and the probability of getting tails in my not-fair coin?

• Jun 21st 2011, 02:22 PM
pickslides
Re: Expected value of a not-fair coin
Do you mean, what is the probability of landing a certain amount of heads from the 10 trials?
• Jun 21st 2011, 02:43 PM
e^(i*pi)
Re: Expected value of a not-fair coin
I got the impression the OP meant that his/her unfair coin would have to be tossed (on average) 10 times before landing on heads once (ie: the first 9 tosses are tails).

Given that what is the chance of getting of a head with a single toss of this unfair coin.

@OP: I suck at stats so I'd not know where to start :(
• Jun 21st 2011, 03:44 PM
pickslides
Re: Expected value of a not-fair coin
Well then the probability of obtaining heads is 1/10 and tails is 9/10.