Mathematics · 2026
JEE Main · 2 April 2026, Shift 1 · Q8
If the mean of the data is 21, then k is one of the roots of the equation:
If the mean of the data
is $\displaystyle 21$, then k is one of the roots of the equation :
| Class | $\displaystyle 5$-$\displaystyle 10$ | $\displaystyle 10$-$\displaystyle 15$ | $\displaystyle 15$-$\displaystyle 20$ | $\displaystyle 20$-$\displaystyle 25$ | $\displaystyle 25$-$\displaystyle 30$ | $\displaystyle 30$-$\displaystyle 35$ |
| Frequency | $\displaystyle 2$ | k | $\displaystyle 28$ | $\displaystyle 54$ | $\displaystyle \mathrm{k}+1$ | $\displaystyle 5$ |
Official answer
From NTA’s final answer key for this paper.
(3)
$\displaystyle 2 x^2-19 x-10=0$
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JEE Main 2026 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.