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Exercise 1722Combinatorics › Inclusion-exclusionL1Added 3 Nov 2026

Committees by inclusion-exclusion

#IE#committees#at least one

Statement

From 77 men and 55 women, how many committees of 44 contain at least one man?

Hint

Complement: committees with no man (all women).

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Solution

Total. (124)=495\binom{12}{4}=495.

No man. (54)=5\binom{5}{4}=5.

At least one man. 495−5=490495-5=490.

Conclusion. 490490 committees.