Mathematics · 2021
JEE Main · 16 March 2021, Shift 2 · Q86
Consider the statistics of two sets of observations as follows: If the variance of the combined set of these two observations is 17/9, then the value…
Consider the statistics of two sets of observations as follows :
If the variance of the combined set of these two observations is $\displaystyle \frac{17}{9}$, then the value of n is equal to \_\_\_\_.
| Size | Mean | Variance | |
| Observation I | $\displaystyle 10$ | $\displaystyle 2$ | $\displaystyle 2$ |
| Observation II | n | $\displaystyle 3$ | $\displaystyle 1$ |
Official answer
5
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JEE Main 2021 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.