Mathematics · Permutations and Combinations

JEE Main 2025 — 2 April, Morning Shift — Question 32

The number of sequences of ten terms, whose terms are either 00 or 11 or 2,2 , that contain exactly five 11s and exactly three 22 s , is equal to:

  1. Option A:

    18201820

  2. Option B:

    25202520

    Correct
  3. Option C:

    360360

  4. Option D:

    4545

Answer: B

Step-by-step solution

Exactly five 1 s and exactly three 2 s

⇒2\Rightarrow 2 zeros must be used

⇒10\Rightarrow 10 places to arrange 5 ones, 3 twos and 2 zeros

⇒10!2!3!5!=2520\Rightarrow \frac{10!}{2!3!5!}=2520

Answer key and solution verified before publishing.

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Exam
JEE Main 2025
Subject
Mathematics
Chapter
Permutations and Combinations
Topic
Problems based on both permutations and combinations
The number of sequences of ten terms, whose terms are either 0 or 1… | JEE Main 2025 PYQ with Solution · DhiX AI