Probability Question 186
Question: A coin is tossed three times in succession. If E is the event that there are at least two heads and F is the event in which first throw is a head, then $ P( \frac{E}{F} )= $
[MP PET 1996]
Options:
A) $ \frac{3}{4} $
B) $ \frac{3}{8} $
C) $ \frac{1}{2} $
D) $ \frac{1}{8} $
Show Answer
Answer:
Correct Answer: A
Solution:
$ S=HHH,HHT,HTH,THH,HTT,THT,TTH,TTT $
$ n(E)=4,n(F)=4 $ and $ n(E\cap F)=3 $
$ \therefore P( \frac{E}{F} )=\frac{P(E\cap F)}{P(F)}=\frac{3/8}{4/8}=\frac{3}{4}. $
BETA
