## Addition

Rules of binary addition

0 + 0 = 0 0 + 1 = 1 1 + 0 = 1 1 + 1 = 10

Example unsigned binary integer

**Example 01**

0000 0101 ---- 0101

**Example 02**

1000 0101 ---- 1101

**Example 03**

11011000 01010110 -------- 100101110

## Subtraction

Subtraction rules:

0 - 0 = 0 0 - 1 =-1 1 - 0 = 1 1 - 1 = 0

Examples of signed binary subtractions

**Example 01**

0101 -0000 ----- 0101

**Example 02**

0111 -0101 ---- 0010

**Example 03**

01010110 -11011000 -------- 10000010

Interpreting number is negative or positive

- Observe the sign bit (MSB)
- If ‘0’, the number is positive
- If ‘1’, the number is negative