anaother probab

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anaother probab

by vaivish » Mon Jun 02, 2008 8:50 am
Q7:
A certain university will select 1 of 7 candidates eligible to fill a position in the mathematics department and 2 of 10 candidates eligible to fill 2 identical positions in the computer science department. If none of the candidates is eligible for a position in both departments, how many different sets of 3 candidates are there to fill the 3 positions?
A. 42
B. 70
C. 140
D. 165
E. 315
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by VP_RedSoxFan » Mon Jun 02, 2008 9:04 am
The methodology here is to take the number of possibilities for the math job and multiply by the number of possibilities for the cs job.

math = 7 possibilities
cs = 10_C_2 = 10!/(2!(10-2)! = 45

Total ways of filling those 3 positions is 315, [E].

Hope this helps.
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