Question

A network has N subscribers. Each subscriber is connected directly to all
other subscribers.
(a) What is the total number of lines L in the network?
(b) What is the value of L for N = 2, 10, 100, and 1,000?
(c) How many lines must be built to each subscriber?

Answer 1

(a)total no of lines will be N(N-1)/2

(b)when n=2;l=1;
when n=10;l=45;
when n=100;l=4950;
when n=1000'l=499500;

(c)each subscriber connected to n-1 subscribers hence lines built to each subscriber are n-1..:)