Binary Addition
1. **State the problem:** Add the binary numbers $101.011$ and $11.1101$.
2. **Understand binary addition:** Binary addition works like decimal addition but only with digits 0 and 1. The rules are:
- $0 + 0 = 0$
- $0 + 1 = 1$
- $1 + 0 = 1$
- $1 + 1 = 10$ (which means write 0 and carry 1 to the next higher bit)
3. **Align the numbers by the binary point:**
$$
\begin{array}{r}
101.0110 \\
+\ 11.1101
\end{array}
$$
Note: Added a trailing zero to $101.011$ to match the number of fractional digits.
4. **Add from right to left:**
- Fractional part:
- $0 + 1 = 1$
- $1 + 0 = 1$
- $1 + 1 = 10$ (write 0, carry 1)
- $0 + 1 + 1 (carry) = 10$ (write 0, carry 1)
- Integer part:
- $1 + 1 + 1 (carry) = 11$ (write 1, carry 1)
- $0 + 1 + 1 (carry) = 10$ (write 0, carry 1)
- $1 + 0 + 1 (carry) = 10$ (write 0, carry 1)
- Carry 1 remains, write it as the new leftmost bit.
5. **Write the result:**
$$1101.0011$$
6. **Explanation:**
The sum of $101.011_2$ and $11.1101_2$ is $1101.0011_2$.
7. **Optional verification in decimal:**
- $101.011_2 = 5 + 0.25 + 0.125 = 5.375$
- $11.1101_2 = 3 + 0.5 + 0.25 + 0.0625 = 3.8125$
- Sum $= 5.375 + 3.8125 = 9.1875$
- $1101.0011_2 = 8 + 4 + 0 + 1 + 0.0 + 0.0 + 0.125 + 0.0625 = 9.1875$
This confirms the binary addition is correct.