Suppose you flip a coin three times. Find the probability of resulting in two heads.

Question

anonymous · Answer

2/3

anonymous · Answer

The choices are 
A.	1/8
B.	1/4
C.	3/8
D.	1/2

anonymous · Answer

do think about how there are 2 sides to a coin

anonymous · Answer

?

adamaero · Answer

http://www.mathsisfun.com/data/probability-events-independent.html

kirbykirby · Answer

Hints: 2 outcomes (heads or tails)
Each trial is independent of each other
The probability of success (getting heads) is the same on each trial
....
It's a binomial experiment. If $X$ = number of heads, then what you have  is a $\text{Binomial}(n=3, p=1/2)$ distribution.

barrycarter · Answer

Hint: write down all possible results you can get (eg, HHH or HTH or TTT, etc). There are 8 of these. Then count how many have exactly two heads.