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7 women and 9 men are on the faculty in the mathematics department at a school. ch 06 sec 3 ex 32 (a) - combinations how many ways are there to select a committee of five members of the department if at least one woman must be on the committee?

User Morwenn
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Final answer:

To determine the number of ways to select a five-member committee with at least one woman from a department of 7 women and 9 men, subtract the number of all-men committee combinations from the total combinations. The total number is the combination of 16 select 5 minus the combination of 9 select 5, which equals 4242 committees.

Step-by-step explanation:

The student has asked: 'How many ways are there to select a committee of five members of the department if at least one woman must be on the committee?' when considering a department with 7 women and 9 men.

To solve the problem, we will use the concept of combinations. There's a total of 16 faculty members, and the question specifies that the committee must include at least one woman.

The total number of ways to select a committee of five without any restrictions is the combination of 16 faculty members taken 5 at a time, which is:

C(16,5) = 16! / [(16-5)! * 5!]
However, we need at least one woman on the committee, so we must subtract the number of committees that have no women (and therefore, all men)

C(9,5) = 9! / [(9-5)! * 5!]
Therefore, the number of committees with at least one woman is the total number of committees minus the number of all-men committees:

C(16,5) - C(9,5)

When calculating these values, you find:

C(16,5) = 4368

C(9,5) = 126

So, the number of ways to select a committee with at least one woman is:

4368 - 126 = 4242

This represents the total number of possible committees with the desired condition.

User Adelost
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