Twenty switches in an office computer network are to be connected so that each switch has a direct connection to exactly three other switches. How many connections will be necessary?
Please answer fast!!
+247 Each switch has 3 connections so there are 3* 20 = 60 connections, but that counts each connection twice (connecting A to B is the same as connecting B to A) so divide 60 by 2 to get 30 connections.
