Probability Question 137
If a dice is thrown twice, the probability of occurrence of 4 at least once is 1 - (5/6)^2
[UPSEAT 2003]
Options:
A) $ \frac{11}{36} $
B) $ \frac{7}{12} $
C) $ \frac{35}{36} $
D) None of these
Show Answer
Answer:
Correct Answer: A
Solution:
Probability of occurrence of 4 $ =\frac{1}{6} $
Probability of non-occurrence of ‘4’ $ =\frac{5}{6} $
$ \therefore $ Required probability $ ={{}^{2}}C_1( \frac{1}{6} )( \frac{5}{6} )+{{}^{2}}C_2{{( \frac{1}{6} )}^{2}}{{( \frac{5}{6} )}^{0}}=\frac{11}{36} $ .
BETA
