1. **State the problem:** Evaluate the expression $$\frac{17!}{3!(17-3)!}$$ and determine if the result is an integer or not.
2. **Recall the formula:** This expression matches the formula for combinations, which is $$\binom{n}{r} = \frac{n!}{r!(n-r)!}$$ where $n=17$ and $r=3$.
3. **Apply the formula:** Substitute values:
$$\binom{17}{3} = \frac{17!}{3!(17-3)!} = \frac{17!}{3!14!}$$
4. **Simplify the factorial expression:** Expand $17!$ as $17 \times 16 \times 15 \times 14!$ to cancel $14!$ in numerator and denominator:
$$\frac{17 \times 16 \times 15 \times 14!}{3! \times 14!} = \frac{17 \times 16 \times 15 \times \cancel{14!}}{3! \times \cancel{14!}}$$
5. **Calculate $3!$:**
$$3! = 3 \times 2 \times 1 = 6$$
6. **Rewrite the expression:**
$$\frac{17 \times 16 \times 15}{6}$$
7. **Simplify the fraction:**
Divide numerator and denominator by 3:
$$\frac{17 \times \cancel{16} \times 15}{\cancel{6}} = \frac{17 \times 16 \times 15}{6}$$
Actually, better to cancel stepwise:
$$\frac{17 \times 16 \times 15}{6} = 17 \times 16 \times \frac{15}{6}$$
Simplify $\frac{15}{6}$:
$$\frac{15}{6} = \frac{\cancel{15}^{5}}{\cancel{6}^{2}} = \frac{5}{2}$$
8. **Calculate the product:**
$$17 \times 16 \times \frac{5}{2} = 17 \times 16 \times 2.5$$
Calculate $16 \times 2.5$:
$$16 \times 2.5 = 40$$
Then multiply by 17:
$$17 \times 40 = 680$$
9. **Conclusion:** The value is an integer and equals 680.
**Final answer:**
$$\frac{17!}{3!(17-3)!} = 680$$
Combination Evaluation D5Ce2C
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