Probability Question 270
Question: A fair die is thrown twenty times. The probability that on the tenth throw the fourth six appears is
Options:
A) $ \frac{^{20}C_{10}\times 5^{6}}{6^{20}} $
B) $ \frac{120\times 5^{7}}{6^{10}} $
C) $ \frac{84\times 5^{6}}{6^{10}} $
D) None of these
Show Answer
Answer:
Correct Answer: C
Solution:
Desired probability = Probability of getting 3 sixes in first 9 throws $ \times $ getting six in the 10 throw $ ={{}^{9}}C_3{{( \frac{1}{6} )}^{3}}{{( \frac{5}{6} )}^{6}}\times \frac{1}{6} $
BETA
