Question

A finite population consists of four elements: 6, 1, 5, 3. (a) how many different samples of size n = 2 can be selected from this population if you sample without replacement? (sampling is said to be without replacement if an element cannot be selected twice for the same sample.)

Answer 1

Since the order of elements doesn't matter, we use the formula for combination as follows.


`nCk= (n!)/(k!(n-k)!)`

So the number of ways to choose 2 elements from a set of 4 elements would be

`4C2= (4!)/(2!(4-2)!)=6`

Thus the answer is 6.