1. **Problem:** A board of directors has 10 members. We want to elect a president, a vice president, and a secretary in that order. How many ways can this be done?
2. **Formula and rules:** This is a permutation problem because the order of selection matters (president, vice president, secretary are distinct positions).
The number of permutations of selecting $k$ positions from $n$ members is given by:
$$P(n,k) = \frac{n!}{(n-k)!}$$
3. **Calculation:** Here, $n=10$ and $k=3$.
$$P(10,3) = \frac{10!}{(10-3)!} = \frac{10!}{7!}$$
4. **Simplify factorial:**
$$\frac{10!}{7!} = 10 \times 9 \times 8 \times \cancel{7!} / \cancel{7!} = 10 \times 9 \times 8$$
5. **Multiply:**
$$10 \times 9 = 90$$
$$90 \times 8 = 720$$
6. **Answer:** There are **720** ways to elect the president, vice president, and secretary in order.
Board Election E54E96
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