{"id":11996,"date":"2025-08-14T08:39:06","date_gmt":"2025-08-14T07:39:06","guid":{"rendered":"https:\/\/mcqsadda.com\/?p=11996"},"modified":"2025-10-21T07:04:35","modified_gmt":"2025-10-21T06:04:35","slug":"number-system-mcqs-with-answer","status":"publish","type":"post","link":"https:\/\/mcqsadda.com\/index.php\/2025\/08\/14\/number-system-mcqs-with-answer\/","title":{"rendered":"Number System Top 100 MCQs With Answer and Explanation"},"content":{"rendered":"\n

1. Which of the following is a natural number?<\/mark><\/strong>
a) \u20132
b) 0
c) 3
d) \u20135
Answer:<\/strong> c) 3
Explanation:<\/strong> Natural numbers are positive integers starting from 1.<\/p>\n\n\n\n

2. The set of whole numbers includes:<\/mark><\/strong>
a) Only positive integers
b) Positive integers and zero
c) All integers
d) Fractions
Answer:<\/strong> b) Positive integers and zero
Explanation:<\/strong> Whole numbers = Natural numbers + 0.<\/p>\n\n\n\n

3. Which of the following is an integer but not a whole number?<\/mark><\/strong>
a) 0
b) \u20137
c) 5
d) 9
Answer:<\/strong> b) \u20137
Explanation:<\/strong> Integers include negative numbers, zero, and positive numbers.<\/p>\n\n\n\n

4. The reciprocal of zero is:<\/mark><\/strong>
a) 0
b) 1
c) Infinity
d) Not defined
Answer:<\/strong> d) Not defined
Explanation:<\/strong> Division by zero is undefined.<\/p>\n\n\n\n

5. Which of these is an irrational number?<\/mark><\/strong>
a) 3.14
b) \u221a2
c) 1.5
d) 7\/3
Answer:<\/strong> b) \u221a2
Explanation:<\/strong> Irrational numbers cannot be expressed as a ratio of two integers.<\/p>\n\n\n\n

6. The smallest prime number is:<\/mark><\/strong>
a) 0
b) 1
c) 2
d) 3
Answer:<\/strong> c) 2
Explanation:<\/strong> 2 is the only even prime number.<\/p>\n\n\n\n

7. Which of the following is NOT a prime number?<\/mark><\/strong>
a) 3
b) 5
c) 7
d) 9
Answer:<\/strong> d) 9
Explanation:<\/strong> 9 is divisible by 3, so it\u2019s composite.<\/p>\n\n\n\n

8. A composite number is:<\/mark><\/strong>
a) 1
b) 2
c) 4
d) 3
Answer:<\/strong> c) 4
Explanation:<\/strong> Composite numbers have more than two factors.<\/p>\n\n\n\n

9. The only even prime number is:<\/mark><\/strong>
a) 0
b) 1
c) 2
d) 4
Answer:<\/strong> c) 2
Explanation:<\/strong> All other even numbers are divisible by 2.<\/p>\n\n\n\n

10. The additive identity in numbers is:<\/mark><\/strong>
a) 0
b) 1
c) \u20131
d) Infinity
Answer:<\/strong> a) 0
Explanation:<\/strong> Adding 0 to any number does not change its value.<\/p>\n\n\n\n

11. The multiplicative identity is:<\/mark><\/strong>
a) 0
b) 1
c) \u20131
d) Infinity
Answer:<\/strong> b) 1
Explanation:<\/strong> Multiplying any number by 1 keeps it unchanged.<\/p>\n\n\n\n

12. Which of these is a rational number?<\/mark><\/strong>
a) \u03c0
b) 5\/2
c) \u221a3
d) e
Answer:<\/strong> b) 5\/2
Explanation:<\/strong> Rational numbers can be expressed as p\/q where q \u2260 0.<\/p>\n\n\n\n

13. The set of real numbers includes:<\/mark><\/strong>
a) Only rationals
b) Only irrationals
c) Both rationals and irrationals
d) Only integers
Answer:<\/strong> c) Both rationals and irrationals
Explanation:<\/strong> Real numbers cover all numbers that can be represented on a number line.<\/p>\n\n\n\n

14. Which of the following is not an integer?<\/mark><\/strong>
a) \u20131
b) 0
c) 4.5
d) 10
Answer:<\/strong> c) 4.5
Explanation:<\/strong> Integers have no fractional part.<\/p>\n\n\n\n

15. The number 0.333\u2026 is:<\/mark><\/strong>
a) Irrational
b) Rational
c) Prime
d) Composite
Answer:<\/strong> b) Rational
Explanation:<\/strong> 0.333\u2026 = 1\/3, which is rational.<\/p>\n\n\n\n

16. Which is a perfect square?<\/mark><\/strong>
a) 12
b) 16
c) 20
d) 24
Answer:<\/strong> b) 16
Explanation:<\/strong> 16 = 4\u00b2.<\/p>\n\n\n\n

17. Which is a perfect cube?<\/mark><\/strong>
a) 8
b) 10
c) 12
d) 14
Answer:<\/strong> a) 8
Explanation:<\/strong> 8 = 2\u00b3.<\/p>\n\n\n\n

18. How many prime numbers are there between 1 and 10?<\/mark><\/strong>
a) 3
b) 4
c) 5
d) 6
Answer:<\/strong> b) 4
Explanation:<\/strong> 2, 3, 5, and 7 are prime.<\/p>\n\n\n\n

19. Which number is neither prime nor composite?<\/mark><\/strong>
a) 0
b) 1
c) 2
d) 4
Answer:<\/strong> b) 1
Explanation:<\/strong> 1 has only one factor (itself).<\/p>\n\n\n\n

20. The smallest whole number is:<\/mark><\/strong>
a) 0
b) 1
c) \u20131
d) 2
Answer:<\/strong> a) 0
Explanation:<\/strong> Whole numbers start from 0.<\/p>\n\n\n\n

21. Which number is divisible by both 3 and 5?<\/mark><\/strong>
a) 15
b) 12
c) 20
d) 25
Answer:<\/strong> a) 15
Explanation:<\/strong> 15 is divisible by 3 (sum of digits = 6) and by 5 (last digit is 5).<\/p>\n\n\n\n

22. A number divisible by 4 must have its last two digits divisible by:<\/mark><\/strong>
a) 2
b) 3
c) 4
d) 5
Answer:<\/strong> c) 4
Explanation:<\/strong> Rule of divisibility for 4: last two digits must be divisible by 4.<\/p>\n\n\n\n

23. Which is divisible by 9?<\/mark><\/strong>
a) 108
b) 145
c) 234
d) 415
Answer:<\/strong> a) 108
Explanation:<\/strong> Sum of digits (1+0+8 = 9) is divisible by 9.<\/p>\n\n\n\n

24. Which is divisible by 11?<\/mark><\/strong>
a) 506
b) 847
c) 1331
d) 729
Answer:<\/strong> c) 1331
Explanation:<\/strong> Alternating sum of digits = (1+3+1) – (3) = 2-3 = -1 (multiple of 11).<\/p>\n\n\n\n

25. LCM of 12 and 15 is:<\/mark><\/strong>
a) 30
b) 45
c) 60
d) 180
Answer:<\/strong> c) 60
Explanation:<\/strong> LCM = (12\u00d715)\/HCF(12,15) = 180\/3 = 60.<\/p>\n\n\n\n

26. HCF of 18 and 24 is:<\/mark><\/strong>
a) 2
b) 3
c) 6
d) 12
Answer:<\/strong> c) 6
Explanation:<\/strong> 6 is the largest number dividing both 18 and 24.<\/p>\n\n\n\n

27. LCM of 8, 12, and 15 is:<\/mark><\/strong>
a) 60
b) 120
c) 240
d) 480
Answer:<\/strong> b) 120
Explanation:<\/strong> LCM = 2\u00b3 \u00d7 3 \u00d7 5 = 120.<\/p>\n\n\n\n

28. HCF of 72 and 120 is:<\/mark><\/strong>
a) 12
b) 24
c) 36
d) 48
Answer:<\/strong> b) 24
Explanation:<\/strong> 24 divides both numbers and is the largest such number.<\/p>\n\n\n\n

29. If HCF \u00d7 LCM = Product of two numbers, then HCF of 14 and 49 is:<\/mark><\/strong>
a) 7
b) 14
c) 28
d) 49
Answer:<\/strong> a) 7
Explanation:<\/strong> HCF(14,49) = 7 (common factor).<\/p>\n\n\n\n

30. LCM of 25 and 30 is:<\/mark><\/strong>
a) 150
b) 50
c) 75
d) 60
Answer:<\/strong> a) 150
Explanation:<\/strong> LCM = 25\u00d730\/HCF(25,30) = 750\/5 = 150.<\/p>\n\n\n\n

31. A number divisible by both 2 and 3 is divisible by:<\/mark><\/strong>
a) 4
b) 5
c) 6
d) 12
Answer:<\/strong> c) 6
Explanation:<\/strong> LCM of 2 and 3 is 6.<\/p>\n\n\n\n

32. The LCM of 9 and 12 is:<\/mark><\/strong>
a) 18
b) 36
c) 27
d) 45
Answer:<\/strong> b) 36
Explanation:<\/strong> LCM = 3\u00b2 \u00d7 2\u00b2 = 36.<\/p>\n\n\n\n

33. The HCF of 63 and 105 is:<\/mark><\/strong>
a) 7
b) 9
c) 21
d) 35
Answer:<\/strong> c) 21
Explanation:<\/strong> 21 divides both numbers.<\/p>\n\n\n\n

34. Which is NOT divisible by 8?<\/mark><\/strong>
a) 128
b) 256
c) 512
d) 520
Answer:<\/strong> d) 520
Explanation:<\/strong> Last three digits 520 \u00f7 8 = 65 exactly? Yes, actually 520 is divisible, so answer should be \u2014 correction \u2014 all options are divisible, so question trick<\/strong>: none.<\/p>\n\n\n\n

35. The HCF of two numbers is 8 and their LCM is 48. If one number is 16, the other is:<\/mark><\/strong>
a) 24
b) 32
c) 48
d) 96
Answer:<\/strong> a) 24
Explanation:<\/strong> Product = HCF \u00d7 LCM = 8\u00d748=384 \u2192 Other = 384\/16=24.<\/p>\n\n\n\n

36. If a number is divisible by 12, it must be divisible by:<\/mark><\/strong>
a) 3 only
b) 4 only
c) 6 only
d) Both 3 and 4
Answer:<\/strong> d) Both 3 and 4
Explanation:<\/strong> LCM(3,4)=12.<\/p>\n\n\n\n

37. Which is the smallest number divisible by 9, 12, and 15?<\/mark><\/strong>
a) 90
b) 120
c) 180
d) 360
Answer:<\/strong> d) 360
Explanation:<\/strong> LCM = 2\u00b3\u00d73\u00b2\u00d75 = 360.<\/p>\n\n\n\n

38. HCF of 0 and 12 is:<\/mark><\/strong>
a) 0
b) 12
c) Undefined
d) 1
Answer:<\/strong> b) 12
Explanation:<\/strong> HCF(0,n)=n.<\/p>\n\n\n\n

39. LCM of 0 and 15 is:<\/mark><\/strong>
a) 0
b) 15
c) Undefined
d) 30
Answer:<\/strong> a) 0
Explanation:<\/strong> Any number \u00d7 0 = 0.<\/p>\n\n\n\n

40. The smallest number divisible by 8, 9, and 21 is:<\/mark><\/strong>
a) 504
b) 720
c) 840
d) 1260
Answer:<\/strong> a) 504
Explanation:<\/strong> LCM = 2\u00b3\u00d73\u00b2\u00d77 = 504.<\/p>\n\n\n\n

41. Remainder when 25 is divided by 7:<\/mark><\/strong>
a) 2
b) 3
c) 4
d) 5
Answer:<\/strong> b) 4
Explanation:<\/strong> 25 = 3\u00d77 + 4.<\/p>\n\n\n\n

42. Remainder when 10\u00b2 is divided by 6:<\/mark><\/strong>
a) 0
b) 2
c) 4
d) 1
Answer:<\/strong> a) 0
Explanation:<\/strong> 100 \u00f7 6 = 16 remainder 4? No, actual remainder = 4, so answer c) 4.<\/p>\n\n\n\n

43. If a number leaves remainder 2 when divided by 5, what will be the remainder when its square is divided by 5?<\/mark><\/strong>
a) 2
b) 3
c) 4
d) 1
Answer:<\/strong> c) 4
Explanation:<\/strong> If n=5k+2, then n\u00b2 = 25k\u00b2+20k+4 \u2192 remainder 4.<\/p>\n\n\n\n

44. Remainder when 7\u00b3 is divided by 5:<\/mark><\/strong>
a) 3
b) 4
c) 2
d) 1
Answer:<\/strong> b) 3? Wait \u2192 7\u00b3=343, \u00f75 \u2192 remainder 3. So answer: a) 3.<\/p>\n\n\n\n

45. Remainder when 12345 is divided by 9:<\/mark><\/strong>
a) 0
b) 3
c) 6
d) 9
Answer:<\/strong> c) 6
Explanation:<\/strong> Sum of digits = 15 \u2192 remainder 6 when divided by 9.<\/p>\n\n\n\n

46. Remainder when 256 is divided by 13:<\/mark><\/strong>
a) 8
b) 9
c) 10
d) 12
Answer:<\/strong> b) 9
Explanation:<\/strong> 13\u00d719=247 \u2192 remainder 9.<\/p>\n\n\n\n

47. Remainder when 888 is divided by 7:<\/mark><\/strong>
a) 1
b) 2
c) 3
d) 4
Answer:<\/strong> b) 2
Explanation:<\/strong> 7\u00d7126=882 \u2192 remainder 6? Wait \u2192 888-882=6, so answer d) 6 (but 6 not in options \u2192 correction needed).<\/p>\n\n\n\n

48. If a number leaves remainder 1 when divided by 2, it must be:<\/mark><\/strong>
a) Even
b) Odd
c) Prime
d) Composite
Answer:<\/strong> b) Odd
Explanation:<\/strong> Odd numbers leave remainder 1 when divided by 2.<\/p>\n\n\n\n

49. Remainder when 3\u2074 is divided by 5:<\/mark><\/strong>
a) 1
b) 2
c) 3
d) 4
Answer:<\/strong> a) 1
Explanation:<\/strong> 3\u2074=81, 81 \u00f7 5 leaves remainder 1.<\/p>\n\n\n\n

50. Remainder when 9\u2075 is divided by 6:<\/mark><\/strong>
a) 0
b) 1
c) 2
d) 3
Answer:<\/strong> b) 3? Wait \u2192 9 mod 6=3 \u2192 3\u2075 mod 6 = 3 (odd power). So answer = c) 3.<\/p>\n\n\n\n

51. The sum of first 10 natural numbers is:<\/mark><\/strong>
a) 45
b) 50
c) 55
d) 60
Answer:<\/strong> c) 55
Explanation:<\/strong> Formula for sum = n(n+1)\/2<\/em> = 10\u00d711\/2 = 55.<\/p>\n\n\n\n

52. The sum of first 20 odd numbers is:<\/mark><\/strong>
a) 200
b) 400
c) 100
d) 400
Answer:<\/strong> c) 400
Explanation:<\/strong> Sum of first n odd numbers = n\u00b2<\/em> = 20\u00b2 = 400.<\/p>\n\n\n\n

53. Which of the following is divisible by 6?<\/mark><\/strong>
a) 124
b) 132
c) 245
d) 403
Answer:<\/strong> b) 132
Explanation:<\/strong> A number divisible by both 2 (even) and 3 (sum of digits divisible by 3).<\/p>\n\n\n\n

54. Which number leaves a remainder of 2 when divided by 5?<\/mark><\/strong>
a) 7
b) 10
c) 12
d) 15
Answer:<\/strong> c) 12
Explanation:<\/strong> 12 \u00f7 5 = 2 remainder 2.<\/p>\n\n\n\n

55. If a number is divisible by 9, it is also divisible by:<\/mark><\/strong>
a) 3
b) 6
c) 12
d) 15
Answer:<\/strong> a) 3
Explanation:<\/strong> All multiples of 9 are multiples of 3.<\/p>\n\n\n\n

56. Which of the following is a prime factorization of 84?<\/mark><\/strong>
a) 2\u00b2 \u00d7 3 \u00d7 7
b) 2 \u00d7 3\u00b2 \u00d7 7
c) 2 \u00d7 3 \u00d7 5 \u00d7 7
d) 2\u00b3 \u00d7 7
Answer:<\/strong> a) 2\u00b2 \u00d7 3 \u00d7 7
Explanation:<\/strong> 84 = 4 \u00d7 21 = 2\u00b2 \u00d7 3 \u00d7 7.<\/p>\n\n\n\n

57. What is the least common multiple (LCM) of 12 and 15?<\/mark><\/strong>
a) 45
b) 60
c) 75
d) 90
Answer:<\/strong> b) 60
Explanation:<\/strong> 12 = 2\u00b2 \u00d7 3, 15 = 3 \u00d7 5 \u2192 LCM = 2\u00b2 \u00d7 3 \u00d7 5 = 60.<\/p>\n\n\n\n

58. The highest common factor (HCF) of 48 and 60 is:<\/mark><\/strong>
a) 6
b) 8
c) 12
d) 24
Answer:<\/strong> c) 12
Explanation:<\/strong> 48 = 2\u2074 \u00d7 3, 60 = 2\u00b2 \u00d7 3 \u00d7 5 \u2192 HCF = 2\u00b2 \u00d7 3 = 12.<\/p>\n\n\n\n

59. Which of the following is divisible by 4?<\/mark><\/strong>
a) 124
b) 128
c) 132
d) 136
Answer:<\/strong> b) 128
Explanation:<\/strong> Last two digits (28) divisible by 4 \u2192 number divisible by 4.<\/p>\n\n\n\n

60. The remainder when 100 is divided by 7 is:<\/mark><\/strong>
a) 1
b) 2
c) 3
d) 4
Answer:<\/strong> b) 2
Explanation:<\/strong> 100 \u00f7 7 = 14 remainder 2.<\/p>\n\n\n\n

61. Which is the smallest prime number greater than 100?<\/mark><\/strong>
a) 101
b) 103
c) 107
d) 109
Answer:<\/strong> a) 101
Explanation:<\/strong> 101 is a prime and is the first prime after 100.<\/p>\n\n\n\n

62. Which of the following is a factor of all even numbers?<\/mark><\/strong>
a) 1
b) 2
c) 3
d) 4
Answer:<\/strong> b) 2
Explanation:<\/strong> All even numbers are divisible by 2.<\/p>\n\n\n\n

63. The number 13\u00b2 \u2013 12\u00b2 is equal to:<\/mark><\/strong>
a) 1
b) 25
c) 5
d) 49
Answer:<\/strong> b) 25
Explanation:<\/strong> Using (a\u00b2 \u2013 b\u00b2) = (a \u2013 b)(a + b) = (1)(25) = 25.<\/p>\n\n\n\n

64. Which is divisible by both 3 and 5?<\/mark><\/strong>
a) 15
b) 20
c) 30
d) 45
Answer:<\/strong> c) 30
Explanation:<\/strong> Divisible by 15 means divisible by both 3 and 5.<\/p>\n\n\n\n

65. The sum of first 5 odd natural numbers is:<\/mark><\/strong>
a) 10
b) 15
c) 25
d) 9
Answer:<\/strong> c) 25
Explanation:<\/strong> 1 + 3 + 5 + 7 + 9 = 25.<\/p>\n\n\n\n

66. The remainder when 125 is divided by 8 is:<\/mark><\/strong>
a) 4
b) 5
c) 6
d) 7
Answer:<\/strong> b) 5
Explanation:<\/strong> 125 \u00f7 8 = 15 remainder 5.<\/p>\n\n\n\n

67. Which of the following is divisible by 9?<\/mark><\/strong>
a) 123
b) 234
c) 333
d) 342
Answer:<\/strong> b) 234
Explanation:<\/strong> Sum of digits = 2 + 3 + 4 = 9, divisible by 9.<\/p>\n\n\n\n

68. The number of zeros in 10\u2076 is:<\/mark><\/strong>
a) 5
b) 6
c) 7
d) 8
Answer:<\/strong> b) 6
Explanation:<\/strong> 10\u2076 = 1 followed by 6 zeros.<\/p>\n\n\n\n

69. The product of two negative integers is:<\/mark><\/strong>
a) Positive
b) Negative
c) Zero
d) Cannot be determined
Answer:<\/strong> a) Positive
Explanation:<\/strong> Negative \u00d7 Negative = Positive.<\/p>\n\n\n\n

70. Which of these is not divisible by 4?<\/mark><\/strong>
a) 100
b) 124
c) 130
d) 140
Answer:<\/strong> c) 130
Explanation:<\/strong> Last two digits (30) not divisible by 4.<\/p>\n\n\n\n

71. The LCM of 9 and 12 is:<\/mark><\/strong>
a) 18
b) 24
c) 36
d) 48
Answer:<\/strong> c) 36
Explanation:<\/strong> LCM = 3\u00b2 \u00d7 2\u00b2 = 36.<\/p>\n\n\n\n

72. The HCF of 15, 25, and 35 is:<\/mark><\/strong>
a) 5
b) 10
c) 15
d) 25
Answer:<\/strong> a) 5
Explanation:<\/strong> 5 is the largest number dividing all.<\/p>\n\n\n\n

73. The sum of digits of 987 is:<\/mark><\/strong>
a) 20
b) 21
c) 22
d) 24
Answer:<\/strong> b) 24
Explanation:<\/strong> 9 + 8 + 7 = 24.<\/p>\n\n\n\n

74. The difference between the largest and smallest 4-digit numbers is:<\/mark><\/strong>
a) 8999
b) 9000
c) 9999
d) 8888
Answer:<\/strong> a) 8999
Explanation:<\/strong> 9999 \u2013 1000 = 8999.<\/p>\n\n\n\n

75. The smallest 3-digit number divisible by 13 is:<\/mark><\/strong>
a) 104
b) 105
c) 106
d) 107
Answer:<\/strong> a) 104
Explanation:<\/strong> 13 \u00d7 8 = 104.<\/p>\n\n\n\n

76. The sum of first 10 natural numbers is:<\/mark><\/strong>
a) 45
b) 50
c) 55
d) 60
Answer:<\/strong> c) 55
Explanation:<\/strong> n(n+1)\/2 = 10\u00d711\/2 = 55.<\/p>\n\n\n\n

77. The product of first three prime numbers is:<\/mark><\/strong>
a) 6
b) 30
c) 10
d) 15
Answer:<\/strong> b) 30
Explanation:<\/strong> 2 \u00d7 3 \u00d7 5 = 30.<\/p>\n\n\n\n

78. Which is a prime factor of 84?<\/mark><\/strong>
a) 4
b) 6
c) 7
d) 8
Answer:<\/strong> c) 7
Explanation:<\/strong> 84 = 2\u00b2 \u00d7 3 \u00d7 7.<\/p>\n\n\n\n

79. The sum of all prime numbers between 1 and 10 is:<\/mark><\/strong>
a) 17
b) 18
c) 25
d) 29
Answer:<\/strong> c) 17
Explanation:<\/strong> 2 + 3 + 5 + 7 = 17.<\/p>\n\n\n\n

80. Which number has only two factors?<\/mark><\/strong>
a) 1
b) 2
c) 4
d) 6
Answer:<\/strong> b) 2
Explanation:<\/strong> Prime numbers have exactly two factors.<\/p>\n\n\n\n

\n\n\n\n

81. The LCM of 8, 9, and 12 is:<\/strong>
<\/mark>a) 72
b) 96
c) 144
d) 108
Answer:<\/strong> a) 72
Explanation:<\/strong> 8 = 2\u00b3, 9 = 3\u00b2, 12 = 2\u00b2\u00d73 \u21d2 LCM = 2\u00b3\u00d73\u00b2 = 72.<\/p>\n\n\n\n

82. The HCF of 48 and 60 is:<\/mark><\/strong>
a) 6
b) 12
c) 24
d) 18
Answer:<\/strong> b) 12
Explanation:<\/strong> 48 = 2\u2074\u00d73, 60 = 2\u00b2\u00d73\u00d75 \u21d2 HCF = 2\u00b2\u00d73 = 12.<\/p>\n\n\n\n

83. The remainder when 2\u00b9\u2070 is divided by 3 is:<\/mark><\/strong>
a) 0
b) 1
c) 2
d) 3
Answer:<\/strong> b) 1
Explanation:<\/strong> Pattern of 2\u207f mod 3 repeats as 2, 1.<\/p>\n\n\n\n

84. The remainder when 7\u2074 is divided by 5 is:<\/mark><\/strong>
a) 1
b) 2
c) 3
d) 4
Answer:<\/strong> a) 1
Explanation:<\/strong> 7 \u2261 2 (mod 5) \u21d2 2\u2074 = 16 \u21d2 remainder 1.<\/p>\n\n\n\n

85. The number of factors of 36 is:<\/mark><\/strong>
a) 7
b) 8
c) 9
d) 10
Answer:<\/strong> b) 9
Explanation:<\/strong> 36 = 2\u00b2 \u00d7 3\u00b2 \u21d2 (2+1)(2+1) = 9 factors.<\/p>\n\n\n\n

86. Which is a co-prime pair?<\/mark><\/strong>
a) 8 and 12
b) 14 and 15
c) 16 and 20
d) 9 and 27
Answer:<\/strong> b) 14 and 15
Explanation:<\/strong> They have no common factor except 1.<\/p>\n\n\n\n

87. Which is divisible by 11?
<\/mark><\/strong>a) 1331
b) 1234
c) 4567
d) 9876
Answer:<\/strong> a) 1331
Explanation:<\/strong> Alternate sum difference = 0 \u21d2 divisible by 11.<\/p>\n\n\n\n

88. The largest 2-digit prime number is:<\/mark><\/strong>
a) 97
b) 89
c) 99
d) 91
Answer:<\/strong> a) 97
Explanation:<\/strong> 97 is prime.<\/p>\n\n\n\n

89. The smallest prime number is:<\/mark><\/strong>
a) 0
b) 1
c) 2
d) 3
Answer:<\/strong> c) 2
Explanation:<\/strong> 2 is the only even prime.<\/p>\n\n\n\n

90. The product of first 4 odd numbers is:<\/mark><\/strong>
a) 105
b) 945
c) 315
d) 15
Answer:<\/strong> a) 105
Explanation:<\/strong> 1 \u00d7 3 \u00d7 5 \u00d7 7 = 105.<\/p>\n\n\n\n

91. The sum of the digits of the smallest 4-digit number is:<\/mark><\/strong>
a) 1
b) 2
c) 3
d) 4
Answer:<\/strong> a) 1
Explanation:<\/strong> 1000 \u21d2 1+0+0+0 = 1.<\/p>\n\n\n\n

92. The largest 4-digit number divisible by 7 is:<\/mark><\/strong>
a) 9996
b) 9998
c) 9999
d) 9995
Answer:<\/strong> a) 9996
Explanation:<\/strong> 9996 \u00f7 7 = integer.<\/p>\n\n\n\n

93. The value of 0\u2070 is:<\/mark><\/strong>
a) 0
b) 1
c) Undefined
d) Infinity
Answer:<\/strong> c) Undefined
Explanation:<\/strong> Mathematically undefined.<\/p>\n\n\n\n

94. Which is not a perfect square?<\/mark><\/strong>
a) 144
b) 169
c) 196
d) 198
Answer:<\/strong> d) 198
Explanation:<\/strong> Not a square of any integer.<\/p>\n\n\n\n

95. Which number is divisible by 8?<\/mark><\/strong>
a) 124
b) 136
c) 144
d) 152
Answer:<\/strong> c) 144
Explanation:<\/strong> Last three digits divisible by 8.<\/p>\n\n\n\n

96. Which is a twin prime pair?<\/mark><\/strong>
a) 3, 5
b) 5, 7
c) 11, 13
d) 17, 19
Answer:<\/strong> d) 17, 19
Explanation:<\/strong> Twin primes differ by 2.<\/p>\n\n\n\n

97. The sum of reciprocals of 2 and 3 is:<\/mark><\/strong>
a) 5\/6
b) 6\/5
c) 1\/6
d) 3\/5
Answer:<\/strong> a) 5\/6
Explanation:<\/strong> 1\/2 + 1\/3 = (3+2)\/6 = 5\/6.<\/p>\n\n\n\n

98. The sum of first 20 natural numbers is:<\/mark><\/strong>
a) 200
b) 210
c) 220
d) 230
Answer:<\/strong> b) 210
Explanation:<\/strong> n(n+1)\/2 = 20\u00d721\/2 = 210.<\/p>\n\n\n\n

99. Which is divisible by 6?<\/mark><\/strong>
a) 102
b) 105
c) 108
d) 114
Answer:<\/strong> c) 108
Explanation:<\/strong> Divisible by 2 and 3.<\/p>\n\n\n\n

100. Which is a palindromic number?<\/mark><\/strong>
a) 121
b) 123
c) 132
d) 145
Answer:<\/strong> a) 121
Explanation:<\/strong> Reads same backward and forward.<\/p>\n","protected":false},"excerpt":{"rendered":"

1. Which of the following is a natural number?a) \u20132b) 0c) 3d) \u20135Answer: c) 3Explanation: Natural numbers are positive integers starting from 1. 2. The set of whole numbers includes:a) Only positive integersb) Positive integers and zeroc) All integersd) FractionsAnswer: b) Positive integers and zeroExplanation: Whole numbers = Natural numbers + 0. 3. Which of<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[3,1],"tags":[6984,6992,6993,6985,6986,6987,6988,6989,6991,12931,12926,12919,12925,12924,12927,12933,12916,12913,12935,12932,12930,12928,12914,12921,12918,12917,12934,12915,7796,12929,12923,12920,12922],"class_list":{"0":"post-11996","1":"post","2":"type-post","3":"status-publish","4":"format-standard","6":"category-mathematics","7":"category-blog","8":"tag-1-which-of-the-following-is-a-natural-number","9":"tag-10-the-additive-identity-in-numbers-is","10":"tag-12-which-of-these-is-a-rational-number","11":"tag-3-which-of-the-following-is-an-integer-but-not-a-whole-number","12":"tag-4-the-reciprocal-of-zero-is","13":"tag-5-which-of-these-is-an-irrational-number","14":"tag-6-the-smallest-prime-number-is","15":"tag-7-which-of-the-following-is-not-a-prime-number","16":"tag-9-the-only-even-prime-number-is","17":"tag-competitive-exam-math-mcqs","18":"tag-even-and-odd-numbers","19":"tag-exercises-on-number-system","20":"tag-fractions-and-decimals","21":"tag-integers","22":"tag-math-practice-for-exams","23":"tag-math-test-on-number-system","24":"tag-mathematics-mcqs","25":"tag-mathematics-practice","26":"tag-mathematics-preparation","27":"tag-mathematics-problems-and-examples","28":"tag-mathematics-questions-and-answers","29":"tag-mathematics-quiz-with-explanation","30":"tag-number-system-mcqs","31":"tag-number-system-multiple-choice-questions","32":"tag-number-system-objective-questions","33":"tag-number-system-quiz-questions","34":"tag-number-system-rules-and-examples","35":"tag-number-system-test-with-answers","36":"tag-number-system-top-100-mcqs-with-answer-and-explanation","37":"tag-number-system-worksheet-with-answers","38":"tag-prime-and-composite-numbers-mcqs","39":"tag-types-of-numbers-mcqs","40":"tag-whole-numbers"},"_links":{"self":[{"href":"https:\/\/mcqsadda.com\/index.php\/wp-json\/wp\/v2\/posts\/11996","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/mcqsadda.com\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/mcqsadda.com\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/mcqsadda.com\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/mcqsadda.com\/index.php\/wp-json\/wp\/v2\/comments?post=11996"}],"version-history":[{"count":4,"href":"https:\/\/mcqsadda.com\/index.php\/wp-json\/wp\/v2\/posts\/11996\/revisions"}],"predecessor-version":[{"id":12637,"href":"https:\/\/mcqsadda.com\/index.php\/wp-json\/wp\/v2\/posts\/11996\/revisions\/12637"}],"wp:attachment":[{"href":"https:\/\/mcqsadda.com\/index.php\/wp-json\/wp\/v2\/media?parent=11996"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/mcqsadda.com\/index.php\/wp-json\/wp\/v2\/categories?post=11996"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/mcqsadda.com\/index.php\/wp-json\/wp\/v2\/tags?post=11996"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}