- 1. Which number would replace underline mark in the series?

2, 5, 10, 17, ---, 37

A.) 27

B.) 24

C.) 26

D.) 28

Answer: Option 'C'

Here the difference between the consecutive terms is increase by 2

5 - 2 = 3,

10 - 5 = 5,

17 - 10 = 7,

then 17 + 9 = 26.

- 2. Which number would replace underline mark in the series?

1, 6, 26,_____, 426.

A.) 86

B.) 76

C.) 106

D.) 96

Answer: Option 'C'

Here the difference between the consecutive terms is multiplied by 4.

The difference of the two consecutive numbers is 5, 20, .....

5 × 4 = 20

20 × 4 = 80

26 + 80 = 106.

- 3. Which number would replace underline mark in the series?

1, 20, 58, ____, 191.

A.) 105

B.) 115

C.) 111

D.) 116

Answer: Option 'B'

Here the difference between the two consecutive terms is 19, 38, 57, 76

58 + 57 = 115

- 4. 2, 10, 40, 120,____

A.) 240

B.) 360

C.) 470

D.) 210

Answer: Option 'A'

Here the series is a multiplication series.

The order of the multiplication is ×5, ×4, ×3, ×2

120 × 2 = 240

- 5. 18 21 25 18 29 33 18

What numbers should come next ?

A.) 43 18

B.) 41 44

C.) 37 41

D.) 38 41

Answer: Option 'C'

This is a simple addition series with a random number, 18, interpolated as every third number.

In the series, 4 is added to each number except 18, to arrive at the next number

- 6. 20 20 17 17 14 14 11 What numbers should come next ?

A.) 8 8

B.) 8 9

C.) 11 8

D.) 8 9s

Answer: Option 'C'

This is a simple subtraction with repetition series.

It begins with 20, which is repeated, then 3 is subtracted, resulting in 17, which is repeated, and so on.

Rule = (1st no) (1st no) (1st no - 3 = 2nd no) (2nd no repeat) (2nd no - 3 = 3rd no) (3rd no repeat). . .

Now (20) (20) (20 - 3 = 17) (17) (17 - 3 = 14) (14) (14 - 3 = 11) (11) (11 - 3 = 8) (8)

So the answer is e = 11 8.

- 7. 3 13 18 23 28 33

What number should come next?

A.) 38 43

B.) 37 42

C.) 38 44

D.) 39 44

Answer: Option 'A'

In this simple addition series, each number is 5 greater than the previous number.

Rule = (1st no) (1st no + 5 = 2nd no) (2nd no + 5 = 3rd no) . . .

Now (3) (3 + 5 = 8) (8 + 5 = 13) (13 + 5 = 18) (18 + 5 = 23) (23 + 5 = 28) (28 + 5 = 33) (33 + 5 = 38) (38 + 5 = 43)

So the answer is c = 38 43

- 8. Look at this series: 1000, 200, 40, . . .

What number should come next?

A.) 10

B.) **8**

C.) 9

D.) 12

Answer: Option 'B'

This is a simple division series.

Each number is divided by 5.

Rule = (1st number / 5 = 2nd number) (2nd number / 5 = 3rd number)....

Now, (1000 / 5 = 200), (200 / 5 = 40), (40 / 5 = 8)...

So answer is a = 8.

- 9. Look at this series: 7, 10, 8, 11, 9, 12, . . .

What number should come next?

A.) 7

B.) 10

C.) 15

D.) 18

Answer: Option 'B'

This is a simple alternating addition and subtraction series.

In the first pattern, 3 is added;

In the second pattern, 2 is subtracted.

Rule =(1st number) (1st number + 3 = 2nd number) (2nd number - 2 = 3rd number) (3rd number + 3 = 4th number)

Now (7) (7 + 3 = 10) (10 - 2 = 8) (8 + 3 = 11) (11 - 2 = 9) (9 + 3 = 12) (12 - 2 = 10)...

So the answer is b = 10.

- 10. 1, 2, 3, 10, ____, 9802

A.) 199

B.) 999

C.) 99

D.) 298

Answer: Option 'C'

1^{2} + 1 = 2

2^{2} - 1 = 3

3^{2} + 1 = 10

10^{2} - 1 = 99.

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