Here are the possible class C subnets:

Bits	Subnet Mask	CIDR	Subnets	Hosts
0	255.255.255.0	/24	1 network	254
1	255.255.255.128	/25	2	126
2	255.255.255.192	/26	4	62
3	255.255.255.224	/27	8	30
4	255.255.255.240	/28	16	14
5	255.255.255.248	/29	32	6
6	255.255.255.252	/30	64	2

Logic tells us that the more host bits we steal, the more subnets we have, but the less hosts we have available per subnet.

We know from book 1 that we need to follow five simple steps in order to answer any subnetting question.  The five steps are:

1.  How many subnets?

2 to the power of masked bits (and – 2 if subnet zero is not allowed).

2.  How many hosts per subnet?

2 to the power of unmasked bits – 2.

3.  What are the valid subnets?

256 – the rightmost non-zero subnet.

4.  What are the valid hosts per subnet?

5. What is the broadcast address of the subnet?

The first subnet of a class C address we can use involves taking 1 bit of the remaining 8 host bits.  If you aren’t sure of what is happening with the binary numbers then go back to book 1.  For the quick method we won’t have time to write things down in binary.