Figure 1 shows the formula “2 to the power of n” where “n” is the number of bits borrowed. Figure 2 shows the formula calculation from 1 bit borrowed up to 6 bits borrowed. 2 to the 1 power equals 1, 2 to the 2 power equals four, and so on until 2 to the 6 power equals 64. Figure 3 shows the formula “2 to power of n minus 2” where “ne” is the number bits remaining in the host portion. Figure 4 shows the 192.168.1.0/25 subnet. The host bits are highlighted. The formula for the number of valid hosts per subnet is 2 to the 7 minus 2 which equals 126.