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Number of ways = [[0]]

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A car dealership employs $\\var{p}$ salespeople. A salesperson receives £100 for each car they sell.

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Yesterday, the dealership sold $\\var{b}$ cars.

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In how many ways could this happen?

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(Consider two scenarios different if they result in different bonus payments).

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

7/02/2013:

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Finished first draft. A description and more tags needed. Included sc tag.

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We are not interested in the order in which the cars were sold, but in the number of cars each salesperson sold.

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Therefore we are interested in the number of $\\var{b}$-multisets from a set of size $\\var{p}$.

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So the number of possibilities is given by:

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\\[\\binom{\\var{p+b-1}}{\\var{b}}=\\var{ans}\\]

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