Q 1-16, 33, 65, 131, 261, (....)

A - 523

B - 521

C - 613

D - 721

```Answer - A

Explanation

"Each number is twice the preceding one with 1 added or subtracted alternatively.

So, the next number is (2 x 261 + 1) = 523."
```

Q 2-10, 5, 13, 10, 16, 20, 19, (....)

A - 22

B - 40

C - 38

D - 23

```Answer - B

Explanation

"There are two series (10, 13, 16, 19) and (5, 10, 20, 40),
one increasing by 3 and the other multiplied by 2"
```

Q 3-"Find out the wrong number in the given sequence of numbers.
56, 72, 90, 110, 132, 150"

A - 72

B - 110

C - 132

D - 150

```Answer - D

Explanation

"The numbers are 7 x 8, 8 x 9, 9 x 10, 10 x 11, 11 x 12, 12 x 13.
So, 150 is wrong."
```

Q 4-2, 4, 12, 48, 240, (....)

A - 960

B - 1440

C - 1080

D - 1920

```Answer - B

Explanation

"Go on multiplying the given numbers by 2, 3, 4, 5, 6.
So, the correct next number is 1440."
```

Q 5-8, 7, 11, 12, 14, 17, 17, 22, (....)

A - 27

B - 20

C - 22

D - 24

```Answer - B

Explanation

"There are two series (8, 11, 14, 17, 20) and (7, 12, 17, 22)
increasing by 3 and 5 respectively."
```

Q 6-11, 13, 17, 19, 23, 29, 31, 37, 41, (....)

A - 43

B - 47

C - 53

D - 51

```Answer - A

Explanation

Numbers are all primes. The next prime is 43.
```

Q 7-"Find out the wrong number in the series.
7, 8, 18, 57, 228, 1165, 6996"

A - 8

B - 18

C - 57

D - 228

```Answer - D

Explanation

"Let the given numbers be A, B, C, D, E, F, G.
Then,
A, A x 1 + 1,
B x 2 + 2,
C x 3 + 3,
D x 4 + 4,
E x 5 + 5,
F x 6 + 6 are the required numbers.
Clearly, 228 is wrong."
```

Q 8-2, 6, 12, 20, 30, 42, 56, (....)

A - 61

B - 64

C - 72

D - 70

```Answer - C

Explanation

"The pattern is
1 x 2, 2 x 3, 3 x 4, 4 x 5, 5 x 6, 6 x 7, 7 x 8.
So, the next number is 8 x 9 = 72."
```

Q 9-4, -8, 16, -32, 64, (....)

A - 128

B - -128

C - 192

D - -192

```Answer - B

Explanation

"Each number is the proceeding number multiplied by -2.
So, the required number is -128."
```

Q 10-15, 31, 63, 127, 255, (....)

A - 513

B - 511

C - 517

D - 523

```Answer - B

Explanation

"Each number is double the preceding one plus 1.

So, the next number is (255 x 2) + 1 = 511."
```

Q 11-"Find the odd man out.
253, 136, 352, 324, 631, 244"

A - 324

B - 136

C - 352

D - 631

```Answer - A

Explanation

The Sum of the digits in each number, Except 324 is 10.
```

Q 12-"Find out the wrong number in the given sequence of numbers.
5, 16, 6, 16, 7, 16, 9"

A - 9

B - 7

C - 6

D - None of these

```Answer - A

Explanation

"Terms at odd places are 5, 6, 7, 8 etc. and each term at even place is 16.
So, 9 is wrong."
```

Q 13-"Find the odd man out.
6, 9, 15, 21, 24, 28, 30"

A - 28

B - 21

C - 24

D - 30

```Answer - A

Explanation

Each of the numbers except 28, is a multiple of 3.
```

Q 14-"Find out the wrong number in the given sequence of numbers.
52, 51, 48, 43, 34, 27, 16"

A - 27

B - 34

C - 43

D - 48

```Answer - B

Explanation

"Subtract 1, 3, 5, 7, 9, 11 from successive numbers.
So, 34 is wrong."
```

Q 15-"Find out the wrong number in the given sequence of numbers.
36, 54, 18, 27, 9, 18.5, 4.5"

A - 4.5

B - 18.5

C - 54

D - 18

```Answer - B

Explanation

"The terms are alternatively multiplied by 1.5 and divided by 3.
However, 18.5 does not satisfy it."
```