JEE MainMathematicsStatisticsNumerical+4 / −1
The variance of the data
| 0 | 1 | 5 | 6 | 10 | 12 | 17 | |
|---|---|---|---|---|---|---|---|
| 3 | 2 | 3 | 2 | 6 | 3 | 3 |
is .
Numerical answer
View written solutionFree
Correct answer: \(\DFRAC{320}{11}\)
- Given data
The values are: with corresponding frequencies
We use the variance formula for a frequency distribution: where
- Find total frequency
- Find the mean
Compute :
Hence,
- Compute
Since ,
Now calculate term by term:
- For , :
- For , :
- For , :
- For , :
- For , :
- For , :
- For , :
Adding:
- Find the variance
Since this is an integer-type question, the exact variance is:
If the question expects the nearest integer, it is .
- Compare with stored answer
Stored correct answer:
Our computed variance is So the exact answer is not exactly , but its approximate value is .
Therefore, I do not fully agree with the stored answer if exact variance is required.
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