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** Up:** Enumeration Rules
** Previous:** The matching Problem 10/9

How many ways are there of assigning 10 police officers to
3 different tasks:
- Patrol, of which there must be 5.
- Office, of which there must be 2.
- Reserve, of which there will be 3.

We saw how the answer comes out to be:

In general there will
ways
divide up
*n* objects into *r*
different categories so that there will be
*k*_{1} objects in category 1, *k*_{2} in category 2,
and so on (
).

*Susan Holmes*

*1998-12-07*