Series – Railway Reasoning part – 10

1. 170, 197, 226, ? [RRB NTPC 12/02/2021 (Morning)]

(a) 370
(b) 257
(c) 287
(d) 320

Correct Answer: (b) 257

Solution:

13² +1 = 170 ,14² +1 = 197 , 15² + 1 = 226 , 16² +1 = 257

2. 7, 12, (?), 37, 57 [RRB NTPC 15/02/2021 (Morning)]

(a) 17
(b) 27
(c) 19
(d) 22

Correct Answer: (d) 22

Solution:

3. 112, 136, 160, 184, ? [RRB NTPC 15/02/2021 (Morning)]

(a) 200
(b) 202
(c) 210
(d) 208

Correct Answer: (d) 208

Solution:

4. 13, 17, 25, 37, 53, ? [RRB NTPC 15/02/2021 (Evening)]

(a) 69
(b) 63
(c) 73
(d) 65

Correct Answer: (c) 73

Solution:

13 + 4 × 1 = 17 , 17 + 4 × 2 = 25 , 25 + 4 × 3 = 37 , 37 + 4 × 4 = 53, 53 + 4 × 5 = 73

5. 13, 16, 22, 31, 43, ? [RRB NTPC 15/02/2021 (Evening)]

(a) 49
(b) 58
(c) 63
(d) 53

Correct Answer: (b) 58

Solution:

Logic-
13 + 3 = 16 , 16 + 6 = 22 , 22 + 9 = 31 , 31 + 12 = 43 , 43 + 15 = 58

6. 6, 8, 12, 28, ? [RRB NTPC 15/02/2021 (Evening)]

(a) 256
(b) 284
(c) 60
(d) 56

Correct Answer: (b) 284

Solution:

6 + 2 = 8
8 + 2² = 8 + 4 = 12
12 + 4² = 12 + 16 = 28
28 + 16² = 28 + 256 = 284

7. 2B, 4D, 7G, 12L, 19S, 30D, 43Q, ? [RRB NTPC 16/02/2021 (Evening)]

(a) 60H
(b) 64S
(c) 60Z
(d) 63X

Correct Answer: (a) 60H

Solution:

In the given series Addition with prime number
2 + 2 = 4 , 4 + 3 = 7 , 7 + 5 = 12 , 12 + 7 = 19 , 19 + 11 = 30 , 30 + 13 = 43 , 43 + 17 = 60
And B + 2 = D , D + 3 = G , G + 5 = L , L + 7 = S , S + 11 = D , D + 13 = Q , Q + 17 = H

8. Z5LW, W7OY, T9RB, Q11UF, ? [RRB NTPC 16/02/2021 (Evening)]

(a) N15YK
(b) N13XK
(c) N13XJ
(d) N15ZK

Correct Answer: (b) N13XK

Solution:

Logic -
Z - 3 = W , W - 3 = T , T - 3 = Q , Q - 3 = N 5 +2 = 7 , 7 + 2 = 9 , 9 + 2 = 11 , 11 + 2 = 13
L + 3 = O , O + 3 = R , R + 3 = U , U + 3 = X W + 2 = Y , Y + 3 = B , B + 4 = F , F + 5 = K

9. SXC, PVB, OTA, LRZ, ? [RRB NTPC 16/02/2021 (Evening)]

(a) KPP
(b) MXC
(c) MWP
(d) KPY

Correct Answer: (d) KPY

Solution:

Logic-
S - 3 = P , P -1 = O , O - 3 = L , L -1 = K
X - 2 = V , V-2 = T , T-2 = R , R - 2 = P
C - 1 = B , B -1 = A , A -1 = Z , Z-1 = Y

10. Find the missing letter/series to complete the following sequence: [RRB NTPC 17/02/2021 (Morning)]

(a) 8/T
(b) 9/S
(c) R/8
(d) 8/S

Correct Answer: (d) 8/S

Solution:

Letter + 3 = Next Letter
Number – 3 = Next Number
D + 3 = G , G + 3 = J , J + 3 = M , M + 3 = P , P + 3 = S
23 – 3 = 20 , 20 – 3 = 17 , 17 – 3 = 14 , 14 – 3 = 11 , 11 – 3 = 8