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Question
Evaluate each of the following:
Solution
\[\ {}^{10} P_4 = \frac{10!}{(10 - 4)!} \]
\[ = \frac{10!}{6!}\]
\[ = \frac{10(9)(8)(7)(6!)}{6!}\]
\[ = 10 \times 9 \times 8 \times 7 \]
\[ = 5040\]
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