Number Series Questions

New sequence is as follows:

pr1  qr2  pr3  pq4  qr5  rp6  qq7  rp8  qp9  qr10  qp11  qp12

16th from the right  end is 7

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.

Take a look at the below sereies :

1500 - 25 = 1475

1475 - 27 = 1448

1448 - 29 = 1419

1419 - 31 = 1388

1388 - 33 = 1355

1355 - 35 = 1320

It clearly shows 1389 is Wrong Number

Given series is 372, 823, 644, 582, 46?, 8?7

Here the series follow the rule that :
372 = 3+7+2 = 12
823 = 8+2+3 = 13
644 = 6+4+4 = 14
582 = 5+8+2 = 15
46? = 4+6+? = 16 => ? = 6
8?7 = 8+?+7 = 17 => ? = 2

So the missing numbers are 6 and 2

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

Given series follows the rule of

1050/2.5 = 420
420/2.5 = 168
168/2.5 = 67.2
so 67.2/2.5 = 26.88