Determining a Common Prefix
000010100.01111111.00000001.00100000 - 20.127.1.32
000010100.01111111.00000001.01000000 - 20.127.1.64
000010100.01111111.00000001.01100000 - 20.127.1.96
000010100.01111111.00000001.10000000 - 20.127.1.128
000010100.01111111.00000001.10100000 - 20.127.1.160
000010100.01111111.00000001.11000000 - 20.127.1.192
000010100.01111111.00000001.11100000 - 20.127.1.224
000010100.01111111.00000001.00000000 - Common prefix to all of the above addresses
Applying rules 4 and 5, we have 20.127.1.0/24, which represents all addresses.