🎯✨ Practice Exercises - Number System (with Answers) ✨🎯

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🌸 Part A: One Word / Short Answer

Q1. What is the base of binary number system?
📝 Ans: 2

Q2. What digits are used in hexadecimal number system?
📝 Ans: 0–9 and A–F (where A=10, B=11, ..., F=15)

Q3. What is the binary equivalent of decimal number 13?
📝 Ans: 1101

Q4. Define 'byte'.
📝 Ans: A byte is a group of 8 bits.

Q5. What do you call a group of 4 bits?
📝 Ans: Nibble 🧃💁‍♀️

🌈 Part B: Conversions (Decimal ↔ Binary / Octal / Hex)

Q6. Convert 45₁₀ to binary.
📝 Ans:

45 ÷ 2 = 22 R1 22 ÷ 2 = 11 R0 11 ÷ 2 = 5 R1 5 ÷ 2 = 2 R1 2 ÷ 2 = 1 R0 1 ÷ 2 = 0 R1 Answer = 101101

45₁₀ = 101101₂

Q7. Convert 11110₂ to decimal.
📝 Ans:

(1×2⁴) + (1×2³) + (1×2²) + (1×2¹) + (0×2⁰) = 16 + 8 + 4 + 2 + 0 = 30

11110₂ = 30₁₀

Q8. Convert 97₁₀ to octal.
📝 Ans:

97 ÷ 8 = 12 R1 12 ÷ 8 = 1 R4 1 ÷ 8 = 0 R1 Answer = 141

97₁₀ = 141₈

Q9. Convert 7A₁₆ to decimal.
📝 Ans:

7 = 7 × 16¹ = 112 A = 10 × 16⁰ = 10 → 112 + 10 = 122

7A₁₆ = 122₁₀

Q10. Convert 110011₍₂₎ to hexadecimal.
📝 Ans:
Group into 4-bits → 0011 0011
→ 0011 = 3, 0011 = 3

110011₂ = 33₁₆

🧠 Part C: Fill in the Blanks

Q11. The base of hexadecimal number system is _____.
📝 Ans: 16

Q12. A byte consists of _____ bits.
📝 Ans: 8

Q13. The binary equivalent of (19)₁₀ is _____.
📝 Ans: 10011

Q14. In hexadecimal, the digit 'B' represents the decimal value _____.
📝 Ans: 11

Q15. Binary number system uses only _____ and _____.
📝 Ans: 0 and 1

💻 Part D: Application / Reasoning Based

Q16. Why do computers use binary number system?

📝 Ans:
Because computers are made of electronic circuits that have two states — ON and OFF. Binary (0 and 1) perfectly matches this, making it simple and efficient for computers to process data.

Q17. Convert the binary number 1011011 to octal.

📝 Ans:
Group into 3s from right → 010 110 11 → pad left with zero → 010 110 011

010 = 2 110 = 6 011 = 3

✅ Final: 263₈

Q18. Convert hexadecimal number 2F to binary.

📝 Ans:

2 = 0010 F = 1111 Answer = 00101111

✅ 2F₁₆ = 00101111₂

Q19. Write a binary number that represents the decimal number 64.

📝 Ans:

64 ÷ 2 = 32 R0 32 ÷ 2 = 16 R0 16 ÷ 2 = 8 R0 8 ÷ 2 = 4 R0 4 ÷ 2 = 2 R0 2 ÷ 2 = 1 R0 1 ÷ 2 = 0 R1 Answer = 1000000

✅ 64₁₀ = 1000000₂

Q20. Convert 100111101₍₂₎ to hexadecimal.

📝 Ans:
Group into 4s from right → 0001 0011 1101

iniCopyEdit0001 = 1 0011 = 3 1101 = D

100111101₂ = 13D₁₆

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