Final answer:
The probability that Chantel and Clover are chosen as leaders of the cheerleading squad is 1/66, calculated using the combinations formula for a group of 12 girls.
Step-by-step explanation:
The probability that Chantel and Clover are chosen as captain and co-captain of the cheerleading squad can be calculated using combinations, as this is a question from combinatoric probability. The squad consists of 12 girls, and we want to choose 2 leaders from this group without considering the order of selection, which is a combination problem. To calculate the total number of ways to select 2 leaders from 12 girls, we use the combination formula C(n, k) = n! / (k!(n-k)!).
So the total number of ways is C(12, 2) which equals 12! / (2! * 10!) = 66. Now, there is only one way for Chantel and Clover to be selected as leaders together. Thus, the probability is 1/66.
Therefore, the probability that Chantel and Clover are chosen as leaders is 1/66.