1. **State the problem:** We have 7 men and 6 women, total 13 runners. We want to form teams of 8 runners and find the proportion of teams with more women than men.
2. **Total number of teams:** The total ways to choose 8 runners from 13 is given by the combination formula:
$$\binom{13}{8} = \frac{13!}{8!5!}$$
3. **Teams with more women than men:** Since the team size is 8, more women than men means women > men. Possible women counts are 5, 6 (since max women is 6).
4. **Calculate teams with 5 women:** Choose 5 women from 6 and 3 men from 7:
$$\binom{6}{5} \times \binom{7}{3}$$
5. **Calculate teams with 6 women:** Choose 6 women from 6 and 2 men from 7:
$$\binom{6}{6} \times \binom{7}{2}$$
6. **Sum teams with more women:**
$$\binom{6}{5} \times \binom{7}{3} + \binom{6}{6} \times \binom{7}{2}$$
7. **Calculate values:**
$$\binom{13}{8} = \frac{13 \times 12 \times 11 \times 10 \times 9}{5 \times 4 \times 3 \times 2 \times 1} = 1287$$
$$\binom{6}{5} = 6$$
$$\binom{7}{3} = \frac{7 \times 6 \times 5}{3 \times 2 \times 1} = 35$$
$$\binom{6}{6} = 1$$
$$\binom{7}{2} = \frac{7 \times 6}{2} = 21$$
8. **Calculate numerator:**
$$6 \times 35 + 1 \times 21 = 210 + 21 = 231$$
9. **Calculate proportion:**
$$\frac{231}{1287}$$
10. **Simplify fraction:**
$$\frac{231}{1287} = \frac{\cancel{231}^\times 1}{\cancel{231}^\times 5.57}$$
Since 231 divides 1287 exactly 5.57 times, let's find exact simplification:
$$231 = 3 \times 7 \times 11$$
$$1287 = 3 \times 7 \times 61$$
Cancel common factors 3 and 7:
$$\frac{3 \times 7 \times 11}{3 \times 7 \times 61} = \frac{11}{61}$$
**Final answer:** The proportion of teams with more women than men is
$$\boxed{\frac{11}{61}}$$
Teams More Women 952Ba6
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