2.5, 3.5, 9, 40, ?

Find the next number in the above-given series?

The given series follows the pattern that,

18, 97, 26, 91, ?, 83

=> 18 + 8 = 26

=> 97 - 8 = 91

=> 26 + 8 = 34

=> 91 - 8 = 83

Hence, the missing number is 34.

4       30       ?     1440       7195      71940

Here the given series follows a pattern of

4

4 x 10 - 10 = 30

30 x 5 - 5  = 145

145 x 10 - 10 = 1440

1440 x 5 - 5 = 7195

7195 x 10 - 10 = 71940

Hence, the missing number is 145

The given series follows the pattern that,

×5+5,   ×5+5,   ×5+5,   ×5+5,   ×5+5

38 x 5 + 5  = 195

195 x 5 + 5 = 980

980 x 5 + 5 = 4905

4905 x 5 + 5 = 24530

24530 x 5 + 5 = 122655

So the missing number is 980 .

The given series pattern follows

17       9       10       18.5       35       90

× 0.5 + 0.5,   × 1 + 1,   × 1.5 + 1.5,   × 2 + 2,   × 2.5 + 2.5

So here 

17x0.5 + 0.5 = 9

9x1 + 1 = 10

10x1.5 + 1.5 = 16.5

16.5x2 + 2 = 35

35x2.5 + 2.5 = 90

Here the odd man in the given series is 18.5

  4             3             4             7               15        ?
×1-1      ×1+1       ×2-1       ×2+1           ×3-1

15x3 - 1 = 45 - 1 = 44

Here the series follows the pattern that, product of succesive prime numbers i.e,

 2 × 3 = 6

 3 × 5 = 15

 5 × 7 = 35

 7 × 11 = 77

 11 × 13 = 143

 13 × 17 = 221

 17 × 19 = 323

So here in place of 77 the number 63 is written.

So the wrong number is 63.

The series given follow the pattern

+2, +2+4, +2+4+6, +2+4+6+8, +2+4+6+8+10,...

Here ? = 7 + 2 + 4 = 13.

Except Horse, remaining all belong to female category.

Hind - Female Deer

Ewe - Female Sheep

Bitch - Female Dog.