prp  qrp  prr  pqr  qrp  rpr  qqr  rpr  qpr  qrr qpr  qpr

If every third letter starting from the left is replaced by a number beginning with 1 then which letter/ number will be 16th from the right?

The given number sequence is 101, 98, 93, 86, 75, ?

101

101 - 3 = 98

98 - 5 = 93

93 - 7 = 86

86 - 11 = 75

75 - 13 = 62

Here the series follows a pattern that consecutive subtraction of prime numbers.

Hence, the next number in the sequence is 62.

Her the given number series is 11, 17, 39, 85, ?

$$\begin{gathered} 11 \\ 11 + 32 - 3 = 17 \\ 17 + (52 - 3) = 39 \\ 39 + (72 - 3) = 85 \\ 85 + (92 - 3) = 163 \end{gathered}$$

Hence, the next number in the given sequence is 163.

The given number series is 9 7 10 6 11 ?

Here in this we have two number sequences, they are

9, 10, 11, ... and 7, 6, 5, ...

Hence, the next number in the given number series is 6 - 1 = 5.

The given number series is 1 8 36 ? 1100 7701

It follows a pattern that,

1

1 x 3 + 5 = 8

8 x 4 + 4 = 36

36 x 5 + 3 = 183

183 x 6 + 2 = 1100

1100 x 7 + 1 = 7701

Hence, the missing number in the given series is 183.

The given number series is 2, 3, 7, 16, 32, ?

$$\begin{gathered} 2 \\ 2 + 12 = 3 \\ 3 + 22 = 7 \\ 7 + 32 = 16 \\ 16 + 42 = 32 \\ 32 + 52 = 57 \\ \end{gathered}$$

Hence, the next number in the given number series is 57.

The given number series is  21 56 102 160 231 316

21      56       102        160      231       316         416

   +35    +46       +58       +71      +85       +100

        +11      +12       +13      +14      +15

Hence, the next number in the given number series is 316 + 100 = 416.

The given number series is 8, 14, 24, 40, ? .

It follows a pattern that,

8

8 x 1.5 + 2 = 14

14 x 1.5 + 3 = 24

24 x 1.5 + 4 = 40

40 x 1.5 + 5 = 65

Hence, the next number in the given number series is 65.

The given number series follows a pattern that,

$$\begin{gathered} 19 + 12 = 20 (not 21) \\ 20 + 22 = 24 \\ 24 + 32 = 33 \\ 33 + 42 = 49 \\ 49 + 52 = 74 \end{gathered}$$

Hence, the odd number in the given number series is 21.