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Question
To know the opinion of the students about Mathematics, a survey of 200 students was conducted. The data is recorded in the following table:
| Opinion: | Like | Dislike |
| Number of students: | 135 | 65 |
Find the probability that a student chosen at random (i) likes Mathematics (ii) does not like it.
Solution
The total number of trials is 200.
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 liking mathematics.
The number of times A happens is 135.
Therefore, we have
P (A) =`135/200`
= 0.675
(ii) Let B be the event of disliking mathematics.
The number of times B happens is 65.
Therefore, we have
P (B) =`65/200`
= 0.325
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