An employer interviews 10 people for 5 technical support positions in a company, and 5 of the 10 people are men. if all 10 are qualified, in how many ways can the employer fill the technical support positions if exactly 1 is a man?

If 5 of the 10 are men it means that the other five are women. 
If in the technical support positions exactly 1 is a man it means that 4 are women.

The answer is:
C(5, 4)*C(5, 1) = 5*5=25 ways.

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