To determine the number of ways to select six city commissioners from a group of twenty candidates, we need to use the concept of combinations. The formula for combinations is given by:
\[ C(n, k) = \frac{n!}{k!(n-k)!} \]
where \( n \) is the total number of candidates, and \( k \) is the number of candidates to be selected.
We need to determine the number of ways to select six city commissioners from a group of twenty candidates. This is a combination problem where we are choosing \( k \) items from \( n \) items without regard to the order.
The formula for combinations is given by:
\[ C(n, k) = \frac{n!}{k!(n-k)!} \]
where \( n \) is the total number of candidates, and \( k \) is the number of candidates to be selected.
Substitute \( n = 20 \) and \( k = 6 \) into the combination formula:
\[ C(20, 6) = \frac{20!}{6!(20-6)!} = \frac{20!}{6! \cdot 14!} \]
Using the combination formula, we calculate:
\[ C(20, 6) = 38,760 \]