Mathematics for IGCSE & O level - Number (Section 2)

  • 1
    Which of the following is the best example of a rational number?
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    (C)
    22/7
  • 2
    Which of the following numbers has the prime factorization 2 x 3 x 5 x 7?
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    (A)
    210
  • 3
    What is the lowest common multiple (LCM) of 6 and 8?
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    (C)
    24
  • 4
    Which number is a multiple of 7?
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    (A)
    21
  • 5
    If two numbers are relatively prime, what is their HCF?
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    (B)
    1
  • 6
    Which numbers are integers?
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    A
    C
  • 7
    Which of the following is an irrational number?
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    (C)
    π
  • 8
    Identify the correct statement:
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    (B)
    All natural numbers are integers.
  • 9
    Which of these expressions results in a rational number?
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    (B)
    2√2 x √2
  • 10
    What is the value of √64?
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    (C)
    8
  • 11
    Which of the following expressions results in a rational number?
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    (B)
    √2 x √2
  • 12
    Which number is a factor of 48, but not a factor of 36?
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    (D)
    8
  • 13
    What is the reciprocal of 4?
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    (A)
    1/4
  • 14
    Which of the following statements regarding the Highest Common Factor (HCF) and Lowest Common Multiple (LCM) is correct?
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    (C)
    The product of HCF and LCM of two numbers equals the product of the two numbers.
  • 15
    If a = 2^2 x 3 x 5 and b = 2 x 3^2 x 7, what is the HCF of a and b?
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    (B)
    12
  • 16
    What is the next prime number after 19?
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    (B)
    23
  • 17
    What is the HCF of 72 and 108?
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    (C)
    36
  • 18
    Which of the following is the same as 0.75?
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    (C)
    3/4
  • 19
    A number is divisible by both 2 and 3. What can you conclude about the number?
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    (C)
    It is divisible by 6.
  • 20
    What is the value of 3. 5 x 4 - 2?
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    (C)
    14
  • 21
    What is the smallest number that has factors of 2, 3, and 5?
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    (C)
    30
  • 22
    What is the value of 3^2 + 2^3?
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    (B)
    17
  • 23
    Which number is a prime number?
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    (C)
    17
  • 24
    Which of these numbers is both a factor of 60 and a multiple of 3?
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    (B)
    6
  • 25
    What is the result of 12 ÷ (3 + 1) x 2?
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    (B)
    6
  • 26
    Which of these numbers is not a factor of 27?
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    (D)
    6
  • 27
    Which number below is an irrational number?
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    (C)
    2.71828...
  • 28
    Which of the following statements is true?
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    (B)
    All natural numbers are integers.
  • 29
    What is the reciprocal of -3?
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    (C)
    -1/3
  • 30
    Which of the following is an example of a terminating decimal?
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    (C)
    5.81
  • 31
    Which of the following could be written as a fraction?
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    (B)
    0.333...
  • 32
    What is the value of k in 392k, given that 392k is a cube number?
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    (B)
    3
  • 33
    What is the product of prime factors of 27?
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    (B)
    3 x 3 x 3
  • 34
    What is the Highest Common Factor (HCF) of 50 and 64?
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    (B)
    2
  • 35
    If a number is rational, then it can be expressed as:
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    (B)
    A fraction a/b where a and b are integers and b ≠ 0
  • 36
    What is the product of prime factors of 72?
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    (C)
    2^3 x 3^2
  • 37
    What is the LCM of 27 and 63?
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    (B)
    189
  • 38
    What is the product of the prime factors of 25?
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    (B)
    5 x 5
  • 39
    What is the product of prime factors of 12?
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    (C)
    2 x 2 x 3
  • 40
    Which of the following can be written as a fraction?
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    (D)
    0.125
  • 41
    What is the product of prime factors of 198?
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    (B)
    2 x 3^2 x 11
  • 42
    What is the reciprocal of 2/3?
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    (B)
    3/2
  • 43
    Which of the following are the prime factors of 100?
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    A
    C
  • 44
    What is the Lowest Common Multiple (LCM) of 42 and 49?
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    (C)
    294
  • 45
    What is the highest common factor (HCF) of 8 and 12?
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    (B)
    4
  • 46
    What is the product of prime factors of 210?
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    (A)
    2 x 3 x 5 x 7
  • 47
    What is the product of prime factors of 350?
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    (B)
    2 x 5^2 x 7
  • 48
    What is the HCF of 2016 and 10584?
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    (D)
    336
  • 49
    Which is the product of prime factors of 100?
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    (B)
    2^2 x 5^2
  • 50
    What is the value of k in 96k, given that 96k is a square number?
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    (C)
    6