Number Series Questions

The given number series is 10, 6, 8, 15, ?

10

10 x 0.5 + 1 = 6

6 x 1 + 2 = 8

8 x 1.5 + 3 = 15

15 x 2 + 4 = 34

Hence, the next number in the given series is 34.

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.

The given sequence is a combination of three series:
i)1st, 4th, 7th terms i.e, 2, 4, 9
ii)2nd, 5th, 8th terms i.e, 3, 6, 12
iii)3rd, 6th, 9th terms i.e, 4, 8, 16
In each one of i, ii, iii, each term is twice the preceding term.
So, 9 is wrong and must be replaced by (4*2) = 8

The given number series is 22, 11, 33, 16.5, 49.5, ?

22

22 / 2 = 11

11 x 3 = 33

33 / 2 = 16.5

16.5 x 3 = 49.5

49.5 / 2 = 24.75

Hence, the next number series is 24.75.

The given series is 1, 2, 6, 21, 88, ?

1

1 x 1 + 1 = 2

2 x 2 + 2 = 6

6 x 3 + 3 = 21

21 x 4 + 4 = 88

88 x 5 + 5 = 445

Hence, the next number in the given number sequence is 445.

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 series follows a pattern that,

-9², +8², -7², +6², -5²