If for some x R, the frequency distribution of the marks obtained by 20 students in a…
Mathematics · JEE Main · NTA Exams — Statistics and Probability
If for some x ∈ R, the frequency distribution of the marks obtained by 20 students in a test is:
| Marks | 2 | 3 | 5 | 7 |
| Frequency | (x + 1)2 | 2x - 5 | x2 - 3x | x |
then the mean of the marks is
- 3.0
- 2.8
- 2.5
- 3.2
Answer
(B) 2.8
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