Binary Operations
1. **Problem i:** Perform the binary subtraction $10000010_2 - 01010111_2$.
2. Convert both binary numbers to decimal to understand the operation:
$$10000010_2 = 1\times2^7 + 0 + 0 + 0 + 0 + 0 + 1\times2^1 + 0 = 128 + 2 = 130$$
$$01010111_2 = 0 + 1\times2^6 + 0 + 1\times2^4 + 0 + 1\times2^2 + 1\times2^1 + 1 = 64 + 16 + 4 + 2 + 1 = 87$$
3. Subtract in decimal: $130 - 87 = 43$.
4. Convert $43$ back to binary:
$$43 = 32 + 8 + 2 + 1 = 2^5 + 2^3 + 2^1 + 2^0$$
So,
$$43_{10} = 00101011_2$$
5. **Answer for i:**
$$10000010_2 - 01010111_2 = 00101011_2$$
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6. **Problem ii:** Divide binary number $11010101_2$ by $101_2$ using long division.
7. Convert divisor and dividend to decimal for clarity:
$$11010101_2 = 213_{10}$$
$$101_2 = 5_{10}$$
8. Perform decimal division:
$$213 \div 5 = 42 \text{ remainder } 3$$
9. Now perform binary long division step-by-step:
- Divisor: $101_2$ (5 decimal)
- Dividend: $11010101_2$
10. Align divisor under the leftmost bits of dividend and subtract if possible, shifting right each time.
11. The quotient in binary is $101010_2$ (which is 42 decimal), and the remainder is $11_2$ (which is 3 decimal).
12. **Answer for ii:**
Quotient = $101010_2$
Remainder = $11_2$
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13. **Problem iii:** Divide $1011010_2$ by $10_2$.
14. Dividing by $10_2$ (which is 2 decimal) in binary is equivalent to shifting right by 1 bit.
15. So,
$$1011010_2 \div 10_2 = 101101_2$$
16. The remainder is the last bit shifted out, which is $0$.
17. **Answer for iii:**
Quotient = $101101_2$
Remainder = $0$