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Question
In a cricket match, a batsman hits a boundary 6 times out of 30 balls he plays.
(i) he hits boundary
(ii) he does not hit a boundary.
Solution
The total number of trials is 30.
Remember the empirical or experimental or observed frequency approach to probability.
If n be the total number of trials of an experiment and A is an event associated to it such that A happens in m-trials. Then the empirical probability of happening of event A is denoted by P(A) and is given by
P(A) =`m/n`
(i) Let A be the event of hitting boundary.
The number of times A happens is 6.
Therefore, we have
P(A) =`6/30`
= 0.2
(ii) Let B be the event of does not hitting boundary.
The number of times B happens is30-6=24 .
Therefore, we have
P(B) =`24/30`
= 0.8
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