1. **Problem statement:** Three runners compete in a race. We want to find the number of ways they can finish the race under two conditions:
a) No tied places.
b) Tied places allowed.
2. **Case a: No tied places**
When no ties are allowed, each runner must have a unique finishing position (1st, 2nd, 3rd).
The number of ways to arrange $n$ distinct items is given by the factorial formula:
$$n! = n \times (n-1) \times (n-2) \times \cdots \times 1$$
For 3 runners, the number of ways is:
$$3! = 3 \times 2 \times 1 = 6$$
3. **Case b: Tied places allowed**
When ties are allowed, the problem becomes counting the number of weak orders or total preorders on 3 elements.
The number of ways to rank $n$ items allowing ties is given by the $n$th ordered Bell number (also called Fubini number).
For $n=3$, the ordered Bell number is 13.
This counts all possible rankings including all tie combinations.
4. **Summary:**
- No ties: 6 ways
- Ties allowed: 13 ways
Thus, the answers are:
$$\boxed{6}$$ ways with no ties
$$\boxed{13}$$ ways with ties allowed
Race Placements 4Ae7A7
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