If you have 5 questionnaires you want to hand out to a group of people,how many combinations of these 5 questionnaires,taking 3 at a time,are there?
A)5
B)20
C)9
D)10

Question

Quizplus · Accepted Answer

The number of combinations of taking 3 questionnaires out of 5 is given by the formula: 
nCr = n! / (r! * (n-r)!)
where n is the total number of questionnaires (5) and r is the number of questionnaires being chosen (3). 
So, the number of combinations is:
5C3 = 5! / (3! * (5-3)!) = 10 
Therefore, the answer is D, 10.

If You Have 5 Questionnaires You Want to Hand Out