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प्रश्न
what is the probability of getting at least two heads?
उत्तर
The total number of trials is 200.
Let A be the event of getting atleast two heads.
The number of times A happens is 72 + 23 = 95 .
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`
Therefore, we have
`P (A) = 95/200`
= `19/40`
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