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Question
Three coins are tossed simultaneously 200 times with the following frequencies of different outcomes:
| Outcome | 3 heads | 2 heads | 1 head | No head |
| Frequency | 23 | 72 | 77 | 28 |
Find the probability of getting at most two heads.
Solution
The total number of trials is 200.
Let A be the event of getting at most two heads.
The number of times A happens is 28 + 77 +72 = 177 .
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) = `177/200`.
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