Mathematics · 2021
JEE Main · 27 July 2021, Shift 2 · Q62
Let the mean and variance of the frequency distribution be 6 and 6.8 respectively. If x_3 is changed from 8 to 7, then the mean for the new data will…
Let the mean and variance of the frequency distribution
be $\displaystyle 6$ and $\displaystyle 6.8$ respectively. If $\displaystyle x_3$ is changed from $\displaystyle 8$ to $\displaystyle 7$ , then the mean for the new data will be:
| $\displaystyle x$ : | $\displaystyle x_1=2$ | $\displaystyle x_2=6$ | $\displaystyle x_3=8$ | $\displaystyle x_4=9$ |
| $\displaystyle f$ : | $\displaystyle 4$ | $\displaystyle 4$ | $\displaystyle \alpha$ | $\displaystyle \beta$ |
Official answer
(1)
$\displaystyle \frac{17}{3}$
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JEE Main 2021 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.