1-60The BCD equivalent of 264_{10} is 001001100100_{BCD}. To convert from BCD to decimal, simply reversethe process as shown:BCD AdditionThe procedures followed in adding BCD are the same as those used in binary. There is, however, thepossibility that addition of BCD values will result in invalid totals. The following example shows this:Add 9 and 6 in BCD:The sum 1111_{2} is the binary equivalent of 15_{10}; however, 1111 is not a valid BCD number. Youcannot exceed 1001 in BCD, so a correction factor must be made. To do this, you add 6_{10} (0110_{BCD}) to thesum of the two numbers. The "add 6" correction factor is added to any BCD group larger than 1001_{2}.Remember, there is no 1010_{2}, 1011_{2}, 1100_{2}, 1101_{2}, 1110_{2}, or 1111_{2} in BCD:The sum plus the add 6 correction factor can then be converted back to decimal to check the answer.Put any carries that were developed in the add 6 process into a new 4-bit word:Now observe the addition of 60_{10} and 55_{10} in BCD: