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Question
The percentage of attendance of different classes in a year in a school is given below:
| Class: | X | IX | VIII | VII | VI | V |
| Attendance: | 30 | 62 | 85 | 92 | 76 | 55 |
What is the probability that the class attendance is more than 75%?
Options
`1/6`
`1/3`
`5/6`
`1/2`
Solution
The total number of trials is 6.
Let A be the event that the attendance of a class is more than 75%.
The number of times A happens is 3 (for classes’ VIII, VII and VI).
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) = 3/6 `
`=1/2`
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