.
There are 13 female board members and 17 male board members.
(a) How many ways are there to make a committee of 18 board members?
(b) How many ways are there to make a committee of 18 board members if exactly 7 must be female?
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Part (a)
There are 13 + 17 = 30 board members, in all.
There are
different ways to select a committee of 18 board members.
Here
is the number of combinations of 30 persons taken 18 at a time.
The formula to calculate it is this
=
=
=
= 86493225. ANSWER
Part (b)
A committee of 18 board members, which includes 7 females, should include 18-7 = 11 males.
7 females from 13 females can be chosen in
= 1716 different ways.
11 males from 17 males can be chosen in
= 12376 different ways.
Combining these different teams, consisting of 11 males and 7 females,
we have 1716*12376 = 21237216 different ways to make such a committee which is required in part (b).
Solved.
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This problem is on COMBINATIONS.
On Combinations, see introductory lessons
- Introduction to Combinations
- PROOF of the formula on the number of Combinations
- Problems on Combinations
- Fundamental counting principle problems
in this site.
Also, you have this free of charge online textbook in ALGEBRA-II in this site
- ALGEBRA-II - YOUR ONLINE TEXTBOOK.
The referred lessons are the part of this online textbook under the topic "Combinatorics: Combinations and permutations".
Save the link to this textbook together with its description
Free of charge online textbook in ALGEBRA-II
https://www.algebra.com/algebra/homework/complex/ALGEBRA-II-YOUR-ONLINE-TEXTBOOK.lesson
into your archive and use when it is needed.