Probability Ques 121
India plays two matches each with West Indies and Australia. In any match the probabilities of India getting points $0,1$ and $2$ 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
$(1992,2 M)$
(a) $0.8750$
(b) $0.0875$
(c) $0.0625$
(d) $0.0250$
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Answer:
Correct Answer: 121.(b)
Solution:
Formula:
- India play $4$ matches and getting at least $7$ points. It can only be possible in $W W W D$ or $W W W W$ position, where $W$ represents two points and $D$ represents one point.
Therefore, the probability of the required event
$ ={ }^{4} C _3(0.05)(0.5)^{3}+{ }^{4} C _4(0.5)^{4} $
$=[4(0.05) + 0.5] $ $(0.5)^{3}$ $=0.0875$
BETA
