Mathematics · 2026
JEE Main · 28 January 2026, Shift 1 · Q9
Let S ={1,2,3,4,5,6,7,8,9}. Let x be the number of 9-digit numbers formed using the digits of the set S such that only one digit is repeated and it…
Let $\displaystyle \mathrm{S}=\{1,2,3,4,5,6,7,8,9\}$. Let $\displaystyle x$ be the number of $\displaystyle 9$-digit numbers formed using the digits of the set S such that only one digit is repeated and it is repeated exactly twice. Let $\displaystyle y$ be the number of $\displaystyle 9$-digit numbers formed using the digits of the set S such that only two digits are repeated and each of these is repeated exactly twice. Then,
Official answer
From NTA’s final answer key for this paper.
(2)
$\displaystyle 21 x=4 y$
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JEE Main 2026 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.