In an experiment involving a treatment applied to 5 test sub

In an experiment involving a treatment applied to 5 test subjects, researchers plan to use a simple random sample of 5 subjects selected from a pool of 7 available subjects. How many different random samples are possible?

Solution

Total available subjects =7

Required Subjects for the experiment = 5

Number different random samples of 5 to be picked from 7 subjects = ⁷C₅ = 21 samples are possible.

We are using combination formula as we have to select a team of 5 random sample subjects and their order of selectiom is not important.