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Number of ways to form a committee = ?[[0]]

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A company has $\\var{t}$ employees, $\\var{m}$ males and $\\var{f}$ females.

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How many ways are there to form a committee of $\\var{n}$ employees that contains at least one male and one female?

", "tags": ["binomial coefficient", "checked2015", "choosing", "choosing subsets", "combinations", "combinatorics", "counting", "MAS1701", "MAS2216", "sc", "selecting"], "rulesets": {}, "preamble": {"css": "", "js": ""}, "type": "question", "metadata": {"notes": "

7/02.2013:

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Finished first draft. Need a description and more tags. Included sc tag.

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There are $\\displaystyle \\binom{\\var{t}}{\\var{n}}$ in which to form the committee when there are no conditions on the number of males and females needed.

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There are $\\displaystyle \\binom{\\var{f}}{\\var{n}}$ ways to form a committee with no males in it.

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There are $\\displaystyle \\binom{\\var{m}}{\\var{n}}$ ways to form a committee with no females in it.

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This give a total of $\\displaystyle \\binom{\\var{t}}{\\var{n}}-\\displaystyle \\binom{\\var{f}}{\\var{n}}-\\displaystyle \\binom{\\var{m}}{\\var{n}}=\\var{ans}$ ways to form the committee with at least one male and one female in it.

", "contributors": [{"name": "Newcastle University Mathematics and Statistics", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/697/"}]}]}], "contributors": [{"name": "Newcastle University Mathematics and Statistics", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/697/"}]}