Statistics And Probability Question 186
Question: A man draws a card from a pack of 52 playing cards, replaces it and shuffles the pack. He continues this processes until he gets a card of spade. The probability that he will fail the first two times is
[MNR 1980]
Options:
A) $ \frac{9}{16} $
B) $ \frac{1}{16} $
C) $ \frac{9}{64} $
D) None of these
Show Answer
Answer:
Correct Answer: C
Solution:
The required probability is given by $ \frac{{}^{39}C_1}{{}^{52}C_1}\times \frac{{}^{38}C_1}{{}^{51}C_1}\times \frac{{}^{13}C_1}{{}^{52}C_1}=\frac{3}{4}\times \frac{13}{51}\times \frac{1}{4}=\frac{13}{68}. $
BETA
