When subnetting, when you want to define how many subnets you need, it's simply the smallest "n" such that 2^n provides at least the number of subnets you want to break the current subnet into.

The default subnet masks for Class A, B and C IP addresses are: Table 8 Click on the Image to Enlarge Examining an IP address of 192.168.2.10 with the default Class C subnet mask applied, the network ...