Mathematics · 2020
JEE Main · 7 January 2020, Shift 2 · Q75
If the mean and variance of eight numbers 3,7,9,12,13,20, x and y be 10 and 25 respectively, then x · y is equal to \ \ \ \.
If the mean and variance of eight numbers $\displaystyle 3,7,9,12,13,20, x$ and $\displaystyle y$ be $\displaystyle 10$ and $\displaystyle 25$ respectively, then $\displaystyle x \cdot y$ is equal to
\_\_\_\_.
Official answer
54
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JEE Main 2020 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.