Mathematics · 2021
JEE Main · 26 August 2021, Shift 2 · Q86
Let the mean and variance of four numbers 3,7, x and y(x>y) be 5 and 10 respectively. Then the mean of four numbers 3+2 x, 7+2 y, x+y and x-y is \ \…
Let the mean and variance of four numbers $\displaystyle 3,7, x$ and $\displaystyle y(x>y)$ be $\displaystyle 5$ and $\displaystyle 10$ respectively. Then the mean of four numbers $\displaystyle 3+2 x, 7+2 y, x+y$ and $\displaystyle x-y$ is \_\_\_\_.
Official answer
12
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JEE Main 2021 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.