Elementary Computer Applications- MCQs- Paper- 03- Topics :- Number System & Conversions

 

Elementary Computer Applications- MCQs- Paper- 03

Topics :- Number System & Conversions – 

🔹 Basic Concepts

1. The base of Binary number system is:
A) 2
B) 8
C) 10
D) 16
Answer: A

2. The base of Octal number system is:
A) 2
B) 4
C) 8
D) 16
Answer: C

3. Decimal number system uses digits from:
A) 0–7
B) 0–9
C) 0–15
D) 1–10
Answer: B

4. Hexadecimal number system has base:
A) 8
B) 10
C) 12
D) 16
Answer: D

5. Which digits are used in Binary system?
A) 0–9
B) 0–7
C) 0 and 1
D) 1 and 2
Answer: C

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🔹 Binary Conversions

6. Binary of decimal 10 is:
A) 1001
B) 1010
C) 1110
D) 1100
Answer: B

7. Decimal value of (1011)₂ is:
A) 9
B) 10
C) 11
D) 13
Answer: C

8. Binary of decimal 15 is:
A) 1111
B) 1011
C) 1101
D) 1001
Answer: A

9. (10000)₂ equals decimal:
A) 8
B) 10
C) 16
D) 32
Answer: C

10. Decimal 7 in binary is:
A) 101
B) 110
C) 111
D) 100
Answer: C

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🔹 Octal Conversions

11. Octal digits range from:
A) 0–7
B) 0–8
C) 1–8
D) 0–9
Answer: A

12. Decimal 8 in octal is:
A) 8
B) 10
C) 11
D) 12
Answer: B

13. Decimal value of (17)₈ is:
A) 13
B) 15
C) 17
D) 19
Answer: B

14. Octal of decimal 20 is:
A) 22
B) 24
C) 26
D) 30
Answer: B

15. Binary equivalent of octal 7 is:
A) 111
B) 101
C) 110
D) 100
Answer: A

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🔹 Hexadecimal Conversions

16. Hexadecimal uses how many symbols?
A) 8
B) 10
C) 12
D) 16
Answer: D

17. In hexadecimal, A represents:
A) 9
B) 10
C) 11
D) 12
Answer: B

18. In hexadecimal, F represents:
A) 14
B) 13
C) 15
D) 16
Answer: C

19. Decimal 16 in hexadecimal is:
A) 10
B) F
C) 11
D) 20
Answer: A

20. Decimal value of (1A)₁₆ is:
A) 24
B) 25
C) 26
D) 27
Answer: C

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🔹 Binary ↔ Octal

21. Binary 111 → Octal is:
A) 6
B) 7
C) 5
D) 4
Answer: B

22. Octal 10 → Binary is:
A) 1000
B) 1010
C) 1100
D) 1111
Answer: A

23. Binary 101011 → Octal is:
A) 51
B) 53
C) 55
D) 57
Answer: B

24. Octal 12 → Binary is:
A) 1010
B) 1011
C) 1100
D) 1001
Answer: A

25. Binary to octal grouping is done in sets of:
A) 2
B) 3
C) 4
D) 8
Answer: B

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🔹 Binary ↔ Hexadecimal

26. Binary to hexadecimal grouping size:
A) 2 bits
B) 3 bits
C) 4 bits
D) 8 bits
Answer: C

27. Binary 1111 → Hex is:
A) E
B) F
C) D
D) C
Answer: B

28. Hex A → Binary is:
A) 1010
B) 1110
C) 1100
D) 1001
Answer: A

29. Binary 1100 → Hex is:
A) A
B) B
C) C
D) D
Answer: C

30. Hex 2F → Binary is:
A) 101111
B) 100111
C) 00101111
D) 111100
Answer: C

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🔹 Decimal ↔ Binary / Octal / Hex

31. Decimal 25 in binary:
A) 11001
B) 10101
C) 11101
D) 10011
Answer: A

32. Decimal 32 in binary:
A) 100000
B) 101000
C) 110000
D) 111000
Answer: A

33. Decimal 64 in octal:
A) 100
B) 80
C) 70
D) 110
Answer: A

34. Decimal 255 in hex:
A) FE
B) FF
C) EF
D) F1
Answer: B

35. Decimal 100 in hex:
A) 64
B) 62
C) 66
D) 60
Answer: A

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🔹 Mixed Conversion

36. (1010)₂ in decimal is:
A) 8
B) 9
C) 10
D) 12
Answer: C

37. (77)₈ in decimal is:
A) 49
B) 63
C) 55
D) 56
Answer: B

38. (FF)₁₆ in decimal is:
A) 254
B) 255
C) 256
D) 253
Answer: B

39. (100)₁₆ in decimal is:
A) 64
B) 128
C) 256
D) 512
Answer: C

40. (11111111)₂ in decimal is:
A) 127
B) 128
C) 255
D) 256
Answer: C

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🔹 Concept + Trick Questions

41. Largest single digit in octal system is:
A) 6
B) 7
C) 8
D) 9
Answer: B

42. Largest digit in hexadecimal is:
A) E
B) F
C) G
D) 9
Answer: B

43. How many binary bits equal one hex digit?
A) 2
B) 3
C) 4
D) 8
Answer: C

44. How many binary bits equal one octal digit?
A) 2
B) 3
C) 4
D) 5
Answer: B

45. Base of number system used in computers internally is:
A) Decimal
B) Octal
C) Binary
D) Hex
Answer: C

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🔹 Practice Level

46. Binary of decimal 18:
A) 10010
B) 10100
C) 11000
D) 10001
Answer: A

47. Octal of decimal 9:
A) 10
B) 11
C) 12
D) 13
Answer: B

48. Hex of decimal 31:
A) 1F
B) 2F
C) 1E
D) 2E
Answer: A

49. Decimal value of (1101)₂ is:
A) 11
B) 12
C) 13
D) 14
Answer: C

50. Binary of hexadecimal B is:
A) 1010
B) 1011
C) 1100
D) 1110
Answer: B

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