Question

An experiment involves 31 participants. From these, a group of 5 participants is to be tested under a special condition. How many groups of 5 participants are possible?

Answer 1

Answer:

169911 groups of 5 participants are possible

Step-by-step explanation:

Total no. of participants = 31

We are supposed to find no. of groups of 5 participants are possible

We will use combination over here  :

Formula : $^nC_r=\frac{n!}{r!(n-r)!}$

Substitute r = 5

n = 31

So,no. of groups of 5 participants are possible =$^nC_r$

So,no. of groups of 5 participants are possible:

$\frac{31!}{5!(31-5)!}=169911$

Hence 169911 groups of 5 participants are possible