## What is BCD addition and subtraction?

Here the method is very simple. At first the decimal equivalent of the given Binary Coded Decimal (BCD) codes are found out. Then the 9’s compliment of the subtrahend is done and then that result is added to the number from which the subtraction is to be done.

### How do you subtract in BCD?

To subtract two BCD numbers, we are going to use the 10s complement method. Taking the first number and storing into B, Load 99 into A then subtract the number to get the 9’s complement. After that add 1 with the result to get 10’s complement.

**What is BCD addition example?**

Steps for BCD addition

BCD code for 984 : | 1001 | 0100 |
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Addition : | 1110 | 1101 |

If Invalid BCD then add 6 : | 0110 | 0110 |

Addition : | 10100 | 10011 |

Remaining bits except carry : | 10100 | 0011 |

**What is BCD subtractor?**

A subtractor circuit is required to perform a subtraction operation on two decimal numbers. BCD subtraction is slightly different from BCD addition. Performing subtraction operation by taking the 9’s or 10’s complement of the subtrahend and adding it to the minuend is economical.

## Why do we add 6 in BCD addition?

When performing addition in BCD, if we get an invalid BCD value, we remedy this by adding 6 to our sum. So, we add 6 to fix this.

### Why we have to add 6 in BCD addition?

When you do math in decimal, if a number is larger than 10 you need to take the modulus of 10 and carry to the next row. Similarly, in BCD math, when the result of the addition is larger than 9 you add 6 to skip the 6 remaining “invalid” values and carry to the next digit.

**Which complement is used in BCD subtraction?**

The 9’s complement has to be formed by a circuit that subtracts Notes every BCD number from 9. First Method − The binary 1010 is added to every complemented digit. The carry is discarded after performing the addition. Second Method − The binary 0110 is added before the digit is complemented.

**What complementation is used in BCD subtraction?**

The BCD Subtraction using 10s Complement can be used to perform subtraction by adding the minuend to the 10s Complement of the subtrahend and dropping the carry.

## What should be done in BCD addition when the sum is greater than 9?

But if the sum is greater than 9, we need to add the BCD equivalent of 6 (i.e., 0110) to the first result to get the answer desired.

### What are the rules in performing the binary addition and binary subtraction?

In the case of binary addition, when 1 is added to 1, it is equal to 0, and 1 carries forward to the next high order digit. In the case of binary subtraction, when 1 is subtracted from 0, then we borrow 1 from the next order digit and get the remainder as 1.

**What is the answer to 1010+ 0101?**

(b) The sum of 0101 and 1010 is 1111. So the answer is 1010. So the answer is 1001.

**What is the output of binary addition 10001 11101?**

• 10001 + 11101 = 101110: 1 1 1 0 0 0 1 + 1 1 1 0 1 1 0 1 1 1 0 | • 101101 + 11001 = 1000110: 1 1 1 1 1 0 1 1 0 1 + 1 1 0 0 1 1 0 0 0 1 1 0 |
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• 1110 + 1111 = 11101: 1 1 1 1 1 1 0 + 1 1 1 1 1 1 1 0 1 | • 10111 + 110101 = 1001100: 1 1 1 1 1 1 0 1 1 1 + 1 1 0 1 0 1 1 0 0 1 1 0 0 |

## What is the sum of 0110 and 0101?

1011

the answer is 1011.