Quantrex Quantrex AcademyJEE · NEET · NDA PYQs with solutions Open app
JEE MainMathematicsPermutation and Combination

A committee of 7 members is to be formed from a group of 6 teachers and 5 students. The committee must contain at least 3 teachers and at least 3 students. However, 1 specific teacher and 1 specific student refuse to serve on the committee together. The total number of ways to form the committee is

Options

  1. A124
  2. B150
  3. C250
  4. D100

Correct answer

B. 150

Step-by-step solution

Total number of ways to select 7 members with at least 3 teachers and at least 3 students without any restriction: Case 1: 4 teachers and 3 students Number of ways = ⁶C₄ ⁵C₃ = 15 10 = 150 Case 2: 3 teachers and 4 students Number of ways = ⁶C₃ ⁵C₄ = 20 5 = 100 Total unrestricted ways = 150 + 100 = 250 Now, we find the number of ways where the specific teacher and the specific student are both included in the committee. We must select 5 more members from the remaining 5 teachers and 4 students. To satisfy the overall

Practice Permutation and Combination on Quantrex Academy →

More from Permutation and Combination

All Permutation and Combination questions Full Permutation and Combination list All JEE Main PYQs