Series – Railway Reasoning part – 6

Total Questions: 50

31. KABL, MCDN, OEFP, QGHR, ? [RRB NTPC 29/12/2020 (Morning)]

Correct Answer: (d) SIJT
Solution:

Here the first, second, third and fourth letters of each term are
obtained by adding +2 with the previous term .
So, the fifth term → Q + 2 = S, G + 2 = I, H + 2 = J, R + 2 = T , i.e SIJT

32. 48, 32, 16, ? [RRB NTPC 29/12/2020 (Morning)]

Correct Answer: (c) 0
Solution:

Logic: Num - 16 = Next Num
So, the fourth term = 16 - 16 = 0

33. 1, 27, 125, 343, ? [RRB NTPC 29/12/2020 (Evening)]

Correct Answer: (c) 729
Solution:

The series is the series of cubic values of consecutive odd numbers  ⇒ 1³,3³,5³,7³,9³
So, the fifth term will be 9³ = 729.

34. 1, 9, 25, 49, 81, ? [ RRB NTPC 30/12/2020 (Morning)]

Correct Answer: (c) 121
Solution:

We can see that the sequence is 1²,3²,5²,7²,9²
So, the sixth term will be =11² = 121

35. 3, 13, 23, 43, 53, 73, 83, 103, 113, ? [RRB NTPC 30/12/2020 (Morning)]

Correct Answer: (c) 163
Solution:

In the given series all numbers are prime ending with 3.
So, next will be 163.

36. 70, 72, 78, 80, ? , 88, 94 [RRB NTPC 30/12/2020 (Evening)]

Correct Answer: (c) 86
Solution:

37. 8, ?, 30, 105, 472.5 [RRB NTPC 30/12/2020 (Evening)]

Correct Answer: (d) 12
Solution:

8 × 1.5 = 12 , 12 × 2.5 = 30 30 × 3.5 = 105 and 105 × 4.5 = 472.5

38. Select the combination of letters that when sequentially placed in the blanks will create a repetitive pattern. [RRB NTPC 04/01/2021 (Morning)]

a _ bc _ a _ bcda _ ccd _ bcd _

Correct Answer: (a) a,d,b,b,a,d
Solution:

There are 20 letters in the series. If we break it into groups of 5 each, we observe that in the 1st five letter ‘a’ comes twice, in 2nd ‘b’ comes twice, in 3rd ‘c’ comes twice and so on. So, correct sequence will be
– a a bc d a b bcd a b ccd a bcd d

39. 64, 60, 52, 40, ? , 4 [RRB NTPC 04/01/2021 (Morning)]

Correct Answer: (b) 24
Solution:

64 - 4 = 60, 60 - 8 = 52,
52 - 12 = 40, 40 - 16 = 24, 24 - 20 = 4

40. 2, 6, 12, 20, ?, ? [RRB NTPC 04/01/2021 (Morning)]

Correct Answer: (a) 30, 42
Solution:

2 + 4 = 6, 6 + 6 = 12, 12 + 8 = 20, 20 + 10 = 30, 30 + 12 = 42