CRE 1 - Number Series

Here the series follows as, +4, +6, +8 and so on. So, the missing number will be 23 + 10 = 33.

Hence, option (a).

Here the next numbers are generated as + 6, + 10, + 14 and now it has to be + 18 and the next number will be 32 + 18 = 50.

Hence, option (d).

Here the series follows as 2² + 1, 4² + 1, 6² + 1, and so on. So, the term will be 12² + 1 = 145.

Hence, option (c).

Here the series follows as +5, +7, +9, +11 and so on. So, the term will be 33 + 11 = 44.

Hence, option (b).

Here the series follows as × 1, × 2, × 3, × 4 and so on.

So, the next term will be 48 × 5 = 240.

Hence, 240.

Here the series follows as × 3, × 2, × 3, × 2 and so on. 

So, the term will be 36 × 3 = 108

Hence, option (b).

Here each number is written as the product of 5 and a prime number i.e. 5 × 2, 5 × 3, 5 × 5, 5 × 7, 5 × 11 and so on. 

So, the next term will be 5 × 13 = 65.

Hence, option (a).

The given sequence is the combination of two series    

I ⇒ 5, 10, 17                        
II ⇒ 7, 13, 19

In the first series, +5, +7, +9 follows and in second series, +6 follows

So, the next term will be 17 + 9 = 26.

Hence, option (c).

Here the series follows as -20, -18, -16, -14 -12 and so on. 

So, the next term will be 442 – 12 = 430.

Hence, option (d).

Here the series can be written as (7 × 2 + 1), (15 × 2 + 1), (31 × 2 + 1) and so on. 

So, the next term will be (63 × 2 + 1) = 127.

Hence, 127.