Number Series Questions

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 series is 6, 6, 12, 36, 144, 720, ?

6

6 x 1 = 6

6 x 2 = 12

12 x 3 = 36

36 x 4 = 144

144 x 5 = 720

720 x 6 = 4320

Hence, the next number in the given number series is 4320.

First difference is 6 and second is 12. But if we take third as 18, then fourth difference will be 24. Then 93 can not be the last term.

So we have to take the difference as 6, 12, 24 and 48. 

So Answer is 21+24 = 45 

New sequence is as follows:

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

16th from the right  end is 7

Here the series of the form is x2 - 1, x2 - 2, x2 - 3,...

 53 x 2 - 4 = 106 - 4 = 102

Here the given number series 625, 625, 600, ?, 475, 875 follows a pattern that

625

625 + (0 x 0) = 625

625 - (5 x 5) = 625 - 25 = 600

600 + (10 x 10) = 600 + 100 = 700

700 - (15 x 15) = 700 - 225 = 475

475 + (20 x 20) = 475 + 400 = 875

Hence, the missing number in the given number series is 700.

The given series follows the pattern that

So the missing number is  37 + 38 = 75

75 + 66 = 141

....

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