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Question
The percentage of marks obtained by a student in monthly unit tests are given below :
| Unit Test | l | ll | lll | lV | V | Vl |
| Percentage of marks obtained | 72 | 67 | 69 | 74 | 71 | 76 |
Based on this data find the probability that the student gets
(ii) less than 72% marks in a unit test.
Solution
The total number of tests taken by a student = 6
The Number of times a student gets less than 72% marks in a unit test = 3
P(less than 72% marks in a unit test)
= `"Number of times student gets less than 72% marks in a unit test"/"Total number of tests taken by a student"`
= `3/6 = 1/2`
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