Subnets are created in powers of 2 due to the way netmasks work.
To accomodate 10 addresses, you would need a /28 (255.255.255.240) netmask, which would provide 14 usable IP addresses. Here are the details of that mask in a private network address area (192.168.x.x)
Output from the unix "ipcalc" program:
Address: 192.168.1.0 11000000.10101000.00000001.0000 0000
Netmask: 255.255.255.240 = 28 11111111.11111111.11111111.1111 0000
Wildcard: 0.0.0.15 00000000.00000000.00000000.0000 1111
=>
Network: 192.168.1.0/28 11000000.10101000.00000001.0000 0000
HostMin: 192.168.1.1 11000000.10101000.00000001.0000 0001
HostMax: 192.168.1.14 11000000.10101000.00000001.0000 1110
Broadcast: 192.168.1.15 11000000.10101000.00000001.0000 1111
Hosts/Net: 14 Class C, Private internet
With the /28 netmask, 192.168.1.0 is the network address, and unusable. 192.168.1.15 is the broadcast address, and is also non-assignable. This gives 14 usable addresses. A /29 netmask (one bit less) gives 6 usable addresses.
To create 10 subnets, the size of the subnets would need to be known, and the process is similar, but the subnets would have different start and end addresses.
You can borrow 6 bits. Which would create a 255.255.255.252 subnet mask, but this subnet only contains 2 usable IP addresses. 7 bits would be 255.255.255.254, but that subnet is too small to have any use in the real world.
Thirty bits make up the network portion of a class C address. Three bits are borrowed for the subnet mask. There is also a class A and a class B that are comprised of bits.
Since this is a class B network you have borrowed 8 bits for subnets. This leaves 8 bits left (1 octet) for clients/workstations. That gives you a maximum of 254 clients per subnet.
The subnet mask itself is an IP Address so it is also 32 bits
we need to borrow 7 bits to subnet 172.16.100.0 to have at least 500 hosts and the subnet mask will be 255.255.254.0
There are 16 bits available; it is up to you how many of those bits you reserve for the subnet, and how many for the individual hosts within each subnet.
64 bits
16 bits per block
16 bits per block
192 is equal to 2 bits borrowed 2^2 = 4 the number of subnets and host are 64 because 2 bits borrowed from the 8 bits of a class C network is 6, therfore 2^6 = 64.
Given a Class C network: 200.1.1.0 We want 5 subnets, each with 30 hosts on it. How many bits to borrow ? How many bits to leave? What is the subnet mask? ( in dot notation and in CIDR notation)
16 bits per block . 8 16bit blocks = 128bits