Mathematics
The percentage of marks obtained by a student of class X in four unit tests are given below :
| Unit test | I | II | III | IV |
|---|---|---|---|---|
| Marks secured % | 62 | 69 | 33 | 86 |
A test is selected at random. What is the probability that the student gets 69% marks in the test ?
Probability
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Answer
Total number of unit tests = 4.
Number of tests in which the student secured 69% marks = 1 (Unit test II).
By formula,
Probability of an event =
∴ P(student gets 69% marks) = .
Hence, the required probability = .
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