Number Series
Direction: In each of the following questions a number series is given. A number is given after the series and then (a), (b), (c), (d) and (e) are given. According to the given series, you have to form a new series which begins with the given number, and then answer the question asked.

6 3.0 4.5 2.25 4.0 12 40 (a) (b) (c) (d) (e) Which of the following numbers will come in place of (c) ?

 20.5
 21.5
 33.75
 69.5
 15

View Hint View Answer Discuss in Forum
The given series is in the below pattern ,
First series :
First term = 6
Second term = First term ÷ 2 = 3
Third term = Second term × 1.5 = 4.5
similarly , we can calculate the all next terms .
........... and so on.
Second series :
First term = 40
Second term = First term ÷ 2 = 20
Third term = Second term × 1.5 = 30Correct Option: E
The given series is in the below pattern ,
First series :
First term = 6
Second term = First term ÷ 2
⇒ Second term = 6 ÷ 2 = 3
Third term = Second term × 1.5
⇒ Third term = 3 × 1.5 = 4.5
similarly , we can calculate the all next terms .
........... and so on.
Second series :
First term = 40
Second term = First term ÷ 2
⇒ Second term = 40 ÷ 2 = 20
Third term = Second term × 1.5
⇒ Third term = 20 × 1.5 = 30
Fourth term = Third term ÷ 2
⇒ Fourth term = 30 ÷ 2 = 15
Hence , the place value of (c) is 15 .

4 9 25 103 3 (a) (b) (c) (d) (e) Which of the following numbers will come in place of (c) ?

 391
 81
 91
 79
 None of these

View Hint View Answer Discuss in Forum
The given series is in the below pattern ,
First series :
First term = 4
Second term = First term × 2 + 1 = 9
Third term = Second term × 3  2 = 25
similarly , we can calculate the all next terms .
Second series :
First term = 3
Second term = First term × 2 + 1 = 7
Third term = Second term × 3  2 = 19Correct Option: D
The given series is in the below pattern ,
First series :
First term = 4
Second term = First term × 2 + 1
⇒ Second term = 4 × 2 + 1 = 9
Third term = Second term × 3  2
⇒ Third term = 9 × 3  2 = 25
similarly , we can find the all others terms .
......... and so on .
Second series :
First term = 3
Second term = First term × 2 + 1
⇒ Second term = 3 × 2 + 1 = 7
Third term = Second term × 3  2
⇒ Third term = 7 × 3  2 = 19
Fourth term = Third term × 4 + 3
⇒ Fourth term = 19 × 4 + 3 = 79
Hence , the place value of ( c ) is 79 .

6 10 32 126 2 (a) (b) (c) (d) (e) Which of the following numbers will come in place of (a) ?

 4
 6
 2
 3
 None of these

View Hint View Answer Discuss in Forum
The series is × 2 – 2, × 3 + 2, × 4 – 2,...
The given series is in the below pattern ,
First series :
First term = 6
Second term = First term × 2  2 = 10
Third term = Second term × 3 + 2 = 32
similarly , we can calculate the all next terms .
Second series :
First term = 2
Second term = First term × 2  2
Third term = Second term × 3 + 2Correct Option: C
The given series is in the below pattern ,
First series :
First term = 6
Second term = First term × 2  2
⇒ Second term = 6 × 2  2 = 10
Third term = Second term × 3 + 2
⇒ Third term = 10 × 3 + 2 = 32
similarly , we can find the all others terms .
......... and so on .
Second series :
First term = 2
Second term = First term × 2  2
⇒ Second term = 2 × 2  2 = 2
Hence , the place value of ( a ) is 2 .

7 4 5 9 20 52.5 3 (a) (b) (c) (d) (e) Which of the following numbers will come in place of (c) ?

 4.5
 2
 6
 7
 None of these

View Hint View Answer Discuss in Forum
As per the details in the question the series is in the form of
First series :
First term = 7
Second term = First term × 0.5 + 0.5 = 4
Third term = Second term × 1 + 1 = 5
similarly , we can calculate the all next terms .
Second series :
First term = 3
Second term = First term × 0.5 + 0.5 = 2
Third term = Second term × 1 + 1 = 3Correct Option: C
As per the details in the question the series is in the form of
First series :
First term = 7
Second term = First term × 0.5 + 0.5
⇒ Second term = 7 × 0.5 + 0.5 = 4
Third term = Second term × 1 + 1
⇒ Third term = 4 × 1 + 1 = 5
similarly , we can find the all others terms .
Second series :
First term = 3
Second term = First term × 0.5 + 0.5
⇒ Second term = 3 × 0.5 + 0.5 = 2
Third term = Second term × 1 + 1
⇒ Third term = 2 × 1 + 1 = 3
Fourth term = Third term × 1.5 + 1.5
⇒ Fourth term = 3 × 1.5 + 1.5 = 6
Hence , the place value of ( c ) is 6 .

3 12 30 66 138 282 7 (a) (b) (c) (d) (e) Which of the following numbers will come in place of (b) ?

 34
 70
 46
 62
 None of these

View Hint View Answer Discuss in Forum
As per the details in the question the series is in the form of
First series :
First term = 3
Second term = First term × 2 + 6 = 12
Third term = Second term × 2 + 6 = 30
similarly , we can calculate the all next terms .
Second series :
First term = 7
Second term = First term × 2 + 6 = 20
Third term = Second term × 2 + 6 = 46Correct Option: C
As per the details in the question the series is in the form of
First series :
First term = 3
Second term = First term × 2 + 6
⇒ Second term = 3 × 2 + 6 = 12
Third term = Second term × 2 + 6
⇒ Third term = 12 × 2 + 6 = 30
similarly , we can find the all others terms .
Second series :
First term = 7
Second term = First term × 2 + 6
⇒ Second term = 7 × 2 + 6 = 20
Third term = Second term × 2 + 6
⇒ Third term = 20 × 2 + 6 = 46
Hence , the place value of ( b ) is 46 .