Difference between revisions of "004 Sample Final A, Problem 17"

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|We can at most choose 1 person from the husband and wife pairs.
 
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|So, we have <math>5 \choose 4</math> ways to pick a 4 people from each couple.
 
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[[004 Sample Final A|<u>'''Return to Sample Exam</u>''']]
 
[[004 Sample Final A|<u>'''Return to Sample Exam</u>''']]

Revision as of 16:19, 5 May 2015

How many ways can a committee of four people can be selected from five married couples if no committee is to include both husband-and-wife pairs? (simplify your answer to a single number)

Foundations
Answer:


Solution:

Step 1:
We can at most choose 1 person from the husband and wife pairs.
So, we have ways to pick a 4 people from each couple.
Step 2:
But, then for each couple, we could choose the husband or the wife to serve on the committee.
So, there are ways to select a committee of four people.
Final Answer:
10

Return to Sample Exam