A class had 30 students. The class needs to select 3 represntatives. In how many ways can this be done?

To find the number of ways to select 3 representatives from a class of 30 students, you can use the combination formula, often denoted as "n choose k" or C(n, k), where n is the total number of items to choose from, and k is the number of items to choose.

The formula for combinations is:

C(n, k) = n! / (k! * (n - k)!)

In this case, n = 30 (total number of students) and k = 3 (number of representatives to choose). Plug these values into the formula:

C(30, 3) = 30! / (3! * (30 - 3)!)

Now, calculate the factorials:

C(30, 3) = (30 × 29 × 28) / (3 × 2 × 1)

C(30, 3) = (30 * 29 * 28) / (3 * 2 * 1)

C(30, 3) = 4060

So, there are 4060 ways to select 3 representatives from a class of 30 students.