Team Selection 3A27Fe
1. **Problem statement:** We need to find the number of ways a basketball coach can select his first 5 players from a 15-man basketball team.
2. **Formula used:** This is a combination problem because the order of selection does not matter. The formula for combinations is:
$$ C(n, r) = \frac{n!}{r!(n-r)!} $$
where $n$ is the total number of players, and $r$ is the number of players to select.
3. **Apply the formula:** Here, $n=15$ and $r=5$.
$$ C(15, 5) = \frac{15!}{5!(15-5)!} = \frac{15!}{5!10!} $$
4. **Simplify the factorial expression:**
$$ \frac{15 \times 14 \times 13 \times 12 \times 11 \times 10!}{5! \times 10!} = \frac{15 \times 14 \times 13 \times 12 \times 11}{5!} $$
5. **Calculate $5!$:**
$$ 5! = 5 \times 4 \times 3 \times 2 \times 1 = 120 $$
6. **Calculate numerator:**
$$ 15 \times 14 = 210 $$
$$ 210 \times 13 = 2730 $$
$$ 2730 \times 12 = 32760 $$
$$ 32760 \times 11 = 360360 $$
7. **Divide numerator by denominator:**
$$ \frac{360360}{120} = 3003 $$
**Final answer:** There are $3003$ ways for the coach to select his first 5 players from the 15-man team.