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From a group of 7 men and 6 women, a 5-person committee is to be formed such that at least 3 men are included. In how many ways can this be done?

Difficulty: Medium

Correct Answer: 756

Explanation:

Problem restatement
Select 5 people from 7 men and 6 women with at least 3 men on the committee.


Given data

  • Men = 7, Women = 6
  • Committee size = 5
  • At least 3 men

Concept/Approach
Casework on the number of men: 3 men + 2 women; 4 men + 1 woman; 5 men + 0 women.


Step-by-Step calculation
Case (3M,2W): ⁡7C36C2 = 35 × 15 = 525Case (4M,1W): ⁡7C46C1 = 35 × 6 = 210Case (5M,0W): ⁡7C5 = 21Total ways = 525 + 210 + 21 = 756


Common pitfalls
Including the (2M,3W) case (violates the constraint) or using permutations instead of combinations.


Final Answer
756

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