# (m-1)n+1 persons. m mutual strangers or someone acquainted with n

#### caffeinemachine

##### Well-known member
MHB Math Scholar
Prove that in a room with $(m-1)n+1$ persons, there are $m$ mutual strangers or there is a person who is acquainted with $n$ persons.

Assume that any two persons are either mutually acquainted to each other or are mutually strangers to each other.