Question

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 (a) `0.8750` (b) `0.0875` (c) `0.0625` (d) `0.0250`
A. `0.8750`
B. 0.0875
C. 0.0625
D. `0.0250`

Answer 1

Correct Answer - B
India play 4 matches and getting at least 7 points. It can only be possible in WWWD or WWWW position, where W represents two points and D represents one point. Therefore, the probability of the required event
`overset(4)""C_(3)(0.05)(0.5)^(3)+overset(3)""C_(4)(0.5)^(4)`
`=[4(0.5)+0.5](0.5)^(3)=0.0875`