Number Series


  1. 4, 28, 160, 990, 6970,55832, 502560
    1. 160
    2. 990
    3. 55832
    4. 6970
    5. None of these

  1. View Hint View Answer Discuss in Forum

    4 x 4 + (4 x 3) = 28
    28 x 5 + (5 x 4) =160
    160 x 6 + (6 x 5) = 990
    990 x 7 + (7 x 6) = 6972
    6972 x 8 + (8 x 7) = 55832
    55832 x 9 + (9 x 8) = 502560

    Correct Option: D

    4 x 4 + (4 x 3) = 28
    28 x 5 + (5 x 4) =160
    160 x 6 + (6 x 5) = 990
    990 x 7 + (7 x 6) = 6972
    6972 x 8 + (8 x 7) = 55832
    55832 x 9 + (9 x 8) = 502560


  1. 13, 14, 27, 45, 68, 109, 177
    1. 27
    2. 109
    3. 45
    4. 68
    5. None of these

  1. View Hint View Answer Discuss in Forum

    13 + 14 = 27
    14 + 27 = 41
    27 + 41 = 68
    41 + 68 = 109
    68 + 109 = 117
    So, 45 is the wrong number in this series.

    Correct Option: C

    13 + 14 = 27
    14 + 27 = 41
    27 + 41 = 68
    41 + 68 = 109
    68 + 109 = 117
    So, 45 is the wrong number in this series.



  1. 529, 841, 961, 1296, 1681, 1849, 2209
    1. 1296
    2. 841
    3. 961
    4. 1681
    5. None of these

  1. View Hint View Answer Discuss in Forum

    All nos, in the given series are squeres of odd nos, except 1296
    1296 = (36)2

    Correct Option: A

    All nos, in the given series are squeres of odd nos, except 1296
    1296 = (36)2


Direction: In each of these questions a number series is given. Only one number is wrong in each series. You have to find out the wrong number.

  1. 1 , 3 , 4 , 7 , 11 ,18 , 27 , 47
    1. 4
    2. 11
    3. 18
    4. 7
    5. 27

  1. View Hint View Answer Discuss in Forum

    As per the details in the question the series is in the form of
    The sum of the first two nos. is the third no.
    First term + Second term = Third term
    Second term + Third term = Fourth term
    Similarly , we can calculate all others terms also.

    Correct Option: E

    As per the details in the question the series is in the form of
    The sum of the first two nos. is the third no.
    First term + Second term = Third term
    ⇒ 1 + 3 = 4 ;
    Second term + Third term = Fourth term
    ⇒ 3 + 4 = 7 ;
    Third term + Fourth term = Fifth term
    ⇒ 4 + 7 = 11 ;
    Fourth term + Fifth term = Sixth term
    ⇒ 7 + 11 = 18 ;
    Fifth term + Sixth term = Seventh term
    ⇒ 11 + 18 = 27 is wrong. It should be 29.
    Sixth term + Seventh term = Eighth term
    ⇒ 18 + 29 = 47
    Hence, 27 is wrong. It should be 29.



  1. 3 , 2 , 3 , 6 , 12 , 37.5 , 115.5
    1. 37.5
    2. 3
    3. 6
    4. 2
    5. 12

  1. View Hint View Answer Discuss in Forum

    The given series is in the below pattern,we can see that
    Next term= ( Previous term × variable ) + variable
    First term = 3
    Second term = ( First term × variable ) + 0.5 = ( 3 x 0.5 ) + 0.5 = 2
    Third term = ( Second term × variable ) + 1 = ( 2 x 1 ) + 1 = 3
    Similarly , we can calculate all others terms also.

    Correct Option: E

    The given series is in the below pattern,we can see that
    Next term= ( Previous term × variable ) + variable
    First term = 3
    Second term = ( First term × variable ) + 0.5 = ( 3 x 0.5 ) + 0.5 = 2
    Third term = ( Second term × variable ) + 1 = ( 2 x 1 ) + 1 = 3
    Similarly , we can calculate all others terms also.
    Fourth term = ( Third term × variable ) + 1.5 = ( 3 × 1.5 ) + 1.5 = 6 ;
    Fifth term = ( Fourth term × variable ) + 2 = ( 6 × 2 ) + 2 = 12 ; 12 is wrong. It should be 14.
    Sixth term = ( Fifth term × variable ) + 2.5 = (14 × 2.5 ) + 2.5 = 37.5 ;
    Seventh term = ( Sixth term × variable ) + 3 = ( 37.5 × 3 ) + 3 = 115.5
    Hence, 12 is wrong. It should be 14.