Question
Question: India play two matches each with West Indies and Australia. In any match the probabilities of India ...
India play two matches each with West Indies and Australia. In any match the probabilities of India getting 0, 1 and 2
points are 0.45, 0.05 and 0.50 respectively. Assuming that the outcomes are independent, the probability of India getting at
least 7 points, is -
A
0.0875
B
1/16
C
0.1125
D
None of these
Answer
0.0875
Explanation
Solution
P (E0) = 0.45, P (E1) = 0.05, P (E2) = 0.50
For 7 points there should be at least three instances of 2 points and one of 1 or 2 points.
\ the required probability
= P (E2E2E2E2) + P (E2E2E2E1) + P (E2E2E1E2) + P (E2E1E2E2) + P (E1E2E2E2)
= P (E2)4 + 4{P (E2)}3 . P (E1)
= (0.50)4 + 4(0.50)3 . (0.05) = 0.0875
Hence (1) is correct answer