Question

How many two-person conversations can occur at a party with 150 people?

---------------- conversations

Answer 1

Answer: Hello! if you have 150 people and you want to see how many two-person conversations are, then you need to see the combinatory between 150 and 2.

The combinatory between two numbers A and B is
`(A!)/(B1*(A - B)!)` Where the combinatory between two numbers is all the possible combinations of A into groups of size B.

Then for 150 and 2, we have
`(150!)/(2!*(148!))  = 150*149/2 = 11175 \\`

So you have 11175 possible conversations.