Number Series


Direction: In each of the following questions a number series is given. A number in the series is suppressed by letter ‘A’. You have to find out the number in the place of ‘A’ and use this number to find out the value in the place of the question mark ? in the equation following the series.

  1. 42   62   92   132   A   242   312
    A + 14 = ? × 14
    1. 11 6
      7
    2. 14
    3. 12 5
      7
    4. 12 1
      2
    5. 12 1
      6

  1. View Hint View Answer Discuss in Forum

    As per the details in the question the series is in the form of
    First term = 42
    Second term = First term + 20
    Second term = 42 + 20 = 62
    Third term = Second term + 30
    Third term = 62 + 30 = 92
    Fourth term = Third term + 40
    Fourth term = 92 + 40 = 132
    Fifth term = Fourth term + 50
    Fifth term = 132 + 50 = A
    ∴ A = 182
    So, 182 will come in place of A.

    Correct Option: B

    As per the details in the question the series is in the form of
    First term = 42
    Second term = First term + 20
    Second term = 42 + 20 = 62
    Third term = Second term + 30
    Third term = 62 + 30 = 92
    Fourth term = Third term + 40
    Fourth term = 92 + 40 = 132
    Fifth term = Fourth term + 50
    Fifth term = 132 + 50 = A
    ∴ A = 182
    So 182 will come in place of A.
    now , 182 + 14 = ? + 14

    ⇒ ? = 196=14
    14


  1. 18   24   A   51   72   98   129 
    A × 3 × 4 = ?
    75
    1. 12
    2. 11 23
      35
    3. 12 12
      35
    4. 14 2
      5
    5. 10 2
      7

  1. View Hint View Answer Discuss in Forum

    As per the details in the question the series is in the form of
    First term = 18
    Second term = First term + 6
    Second term = 18 + 6 = 24
    Third term = Second term + 11
    Third term = 24 + 11 = A
    ∴ A = 35
    So 35 will come in place of A.
    Similarly , we can calculate all next terms also.

    Correct Option: A

    As per the details in the question the series is in the form of
    First term = 18
    Second term = First term + 6
    Second term = 18 + 6 = 24
    Third term = Second term + 11
    Third term = 24 + 11 = A
    ∴ A = 35
    Fourth term = Third term + 16
    Fourth term = 35 + 16 = 51

    A × 3 × 4 = ?
    75
    ⇒ ? = 35 × 3 × 4 =12
    7 × 5



  1. 3/8 3/4 9/16 9/827/32 27/16 A
    A = ?
    1. 2/3
    2. 6/8
    3. 6/4
    4. 3/4
    5. 9/8

  1. View Hint View Answer Discuss in Forum

    The given series is in the below pattern,

    First term = 3
    8

    Second term = First term × 2
    Second term = 3 × 2 = 3
    84

    Third term = Second term × 3
    4

    Similarly , we can calculate all others terms also.

    Correct Option: E

    The given series is in the below pattern,

    First term = 3
    8

    Second term = First term × 2
    Second term = 3 × 2 = 3
    84

    Third term = Second term × 3
    4

    Third term = 3 × 3 = 9
    4416

    Fourth term = Third term × 2
    Fourth term = 9 × 2 = 9
    168

    Fifth term = Fourth term × 3
    4

    Fifth term = 9 × 3 = 27
    8432

    Sixth term = Fifth term × 2
    Sixth term = 27 × 2 = 27
    3216

    Seventh term = Sixth term × 3
    4

    Seventh term = 27 × 3 = 81
    16464

    ∴ A = 81/64
    So, 81/64 will come in place of A.
    A = √ 81 = ? ⇒ ? = 9
    648


  1. 36   216   64.8   388.8   A   699.84   209.952
    A ÷ 36 = ?
    1. 61.39
    2. 0.324
    3. 3.24
    4. 6.139
    5. 32.4

  1. View Hint View Answer Discuss in Forum

    The given series is in the below pattern,
    First term = 36
    Second term = First term × 6
    Second term = 36 × 6 = 216
    Third term = Second term × 0.3
    Third term = 216 × 0.3 = 64.8

    Correct Option: C

    The given series is in the below pattern,
    First term = 36
    Second term = First term × 6
    Second term = 36 × 6 = 216
    Third term = Second term × 0.3
    Third term = 216 × 0.3 = 64.8
    Fourth term = Third term × 6
    Fourth term = 64.8 × 6 = 388.8
    Fifth term = Fourth term × 0.3
    Fifth term = 388.8 × 0.3 = A
    ∴ A = 116.64
    So, 116.64 will come in place of A.
    Similarly , we can find all others terms also.
    now , 116.64 ÷ 36 = 3.24



  1. 4   7   12   19   28   A   52
    A2 – 4 = ?
    1. 1365
    2. 1353
    3. 1505
    4. 1435
    5. 1517

  1. View Hint View Answer Discuss in Forum

    The given series is in the below pattern,
    First term = 4
    Second term = First term + 3
    Second term = 4 + 3 = 7
    Third term = Second term + 5
    Third term = 7 + 5 = 12
    Fourth term = Third term + 7
    Fourth term = 12 + 7 = 19
    Similarly , we can calculate all next terms also.

    Correct Option: E

    The given series is in the below pattern,
    First term = 4
    Second term = First term + 3
    Second term = 4 + 3 = 7
    Third term = Second term + 5
    Third term = 7 + 5 = 12
    Fourth term = Third term + 7
    Fourth term = 12 + 7 = 19
    Fifth term = Fourth term + 9
    Fifth term = 19 + 9 = 28
    Sixth term = Fifth term + 11
    Sixth term = 28 + 11 = A
    ∴ A = 39
    So, 39 will come in place of A.
    Similarly , we can find all others terms also.
    now , A2 – 4 = 392 – 4 = 1517
    Hence ? = 1517