Answer:
C. Permutation; number of ways = 120
Explanation:
The order in which the runners finish is important. For example, A,B,C means that A will be awarded the 1st place medal, B the 2nd and C the 3rd. B,A,C means that B is awarded the 1st place medal, A the 2nd and C the 3rd. So we use the permutations formula to solve this question. That is, this is a permutation.
Permutations formula:
The number of possible permutations of x elements from a set of n elements is given by the following formula:
![P_((n,x)) = (n!)/((n-x)!)](https://img.qammunity.org/2021/formulas/mathematics/college/iftsizhotvl3emolg16e3ljeid6iz7usn1.png)
In this question:
3 medals to 6 runners. So
![P_((6,3)) = (6!)/((6-3)!) = 120](https://img.qammunity.org/2021/formulas/mathematics/high-school/lnb5kl2j4qjx1an3jtlmthf00wn30kl3ag.png)
So the correct answer is:
C. Permutation; number of ways = 120