Insert the missing number.

7, 26, 63, 124, 215, 342, (....)

The given number series follows a pattern that

11

11 - 5.5 = 5.5

5.5 + 4.5 = 10

10 - 3.5 = 6.5

6.5 + 2.5 = 9

9 - 1.5 = 7.5

Hence, the next number in the given number series is 7.5.

The given number series is 3, 5, 13, 43, 167

3

3 x 1 + 2 = 5

5 x 2 + 3 = 13

13 x 3 + 4 = 43

43 x 4 + 5 = 177 (not equal to 167)

Hence, the odd number in the given number sequence is 167. 

The given number series is 35, 36, 55, 111, ?

35

35 x 1 + 1 = 36

36 x 1.5 + 1 = 55

55 x 2 + 1 = 111

111 x 2.5 + 1 = 278.5

Hence, the next number in the given number series is 278.5.

Given Series is 5, 14, 42, 107, 233, _?

5, 14, 42, 107, 233, _?

Differences is 9, 28, 65, 126

9 = 2^3 + 1

28 = 3^3 + 1

65 = 4^3 + 1

126 = 5^3 + 1

Now, next difference must be 6^3 + 1 = 217

Hence, next number in the given series = 233 + 217 = 450.

Here the given number series is 270, 261, 279, 252, 289, 243

270 - 9 = 261

261 + 18 = 279

279 - 27 = 252

252 + 36 = 288 (not equals to 289)

288 - 45 = 243

Hence, the odd number in the given number series is 289.

The given number series is 6, 6, 9, 18, 45, ?

Here the series follows a pattern that,

6 

6 x 1 = 6

6 x 1.5 = 9

9 x 2 = 18

18 x 2.5 = 45

45 x 3 = 135

Hence, the next number in the given number series is 135.

The given number series follows a pattern that,

56

56 + 8 = 64

64 - 16 = 48

48 + 32 = 80 (Not equal to 90)

80 - 64 = 16

16 + 128 = 144 

Hence, the odd number in the given number series is 90.

The given number series 410, 409, 413, 404, ? , follows a pattern that 

410

$$\begin{gathered} 410 - 13 = 409 \\ 409 + 22 = 413 \\ 413 - 33 = 404 \\ 404 + 42 = 420 \end{gathered}$$

Hence, the next number in the given series is 420.