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New Member

I have a subnetting question.

I know how to subnet a Class C adress. However, there is a question of a class B adress that I can't figure it out.

This is what I know, this is a simalar question.

What is the broadcas adress of this IP /27 ?

Answer is:

/27=  is 3 bits so increment is 32.  host 33 to 62

broadcast 63.

However, why I can't get the answer of this question? ---->
What is the braodcast adress of this ip The answer is but I don't get that.

This is what I do:

256-240 = 16
so subnets are -   host ranges -
                     broadcast is

What am I doing wrong? how can I get that answer ?

Cisco Employee

Re: I have a subnetting question.

This document does a very good job of explaining subnetting and the math involved:

Based on that, the broadcast address for is:  The host address range is  Your math is incorrect since you subtracted 16 from 32 instead of adding it.