MathDB

In a party, each person knew exactly

22

other persons. For each two persons

X

and

Y

, if

X

and

Y

knew each other, there is no other person who knew both of them, and if

X

and

Y

did not know each other, there are exactly

6

persons who knew both of them. Assume that

X

knew

Y

iff

Y

knew

X

. How many people did attend the party? Yudi Satria, Jakarta

Problem Statement