Permutations & Combinations · JEE Advanced previous year questions

2025 1 question

1. Q102025 · 18 May 2025 · Paper 1· Numerical answer

   Let $S$ be the set of all seven-digit numbers that can be formed using the digits 0, 1 and 2. For example, 2210222 is in $S$, but 0210222 is $\text{NOT}$ in $S$. Then the number of elements $x$ in $S$ such that at least one of the digits 0 and 1 appears exactly twice in $x$, is equal to ____.

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   Answer: 762