This is a little hard...

Level pending

At a party, everyone shook hands with everybody else. There were 66 handshakes. How many people were at the party?


The answer is 12.

A Former Brilliant Member by A Former Brilliant Member

This section requires Javascript.
You are seeing this because something didn't load right. We suggest you, (a) try refreshing the page, (b) enabling javascript if it is disabled on your browser and, finally, (c) loading the non-javascript version of this page . We're sorry about the hassle.

1 solution

Sujoy Roy
Nov 29, 2014

If n n number of people present in the party, then

n C 2 = 66 ^{n}C_2=66

or, n ( n − 1 ) 2 = 66 \frac{n(n-1)}{2}=66

or, n = 12 n=\boxed{12}

0 Helpful 0 Interesting 0 Brilliant 0 Confused

0 pending reports

×

Problem Loading...

Note Loading...

Set Loading...