Series – Railway Reasoning part – 11

Total Questions: 50

1. 5040, 840, 168, 42, 14, ? [RRB NTPC 08/03/2021 (Evening)]

Correct Answer: (c) 7
Solution:

(5040 ÷ 6) = 840
(840 ÷ 5) = 168
(168 ÷ 4) = 42
(42 ÷ 3) = 14
(14 ÷ 2) = 7

2. 3, 3, 9, 15, 33, ?, 129, 255, 513, 1023 [RRB NTPC 08/03/2021 (Evening)]

Correct Answer: (b) 63
Solution:

Logic-
(3 × 2) - 3 = 3 , (3 × 2) + 3 = 9 , (9 × 2) - 3 = 15 , (15 × 2) + 3 = 33 , (33 × 2) - 3 = 63

3. 31J, 29F, 31M, 30A, 31M, 30J, ? [RRB NTPC 08/03/2021 (Evening)]

Correct Answer: (d) 31J
Solution:

4. AZYB, EVUF, IRQJ, MNMN, ? [RRB NTPC 08/03/2021 (Evening) ]

Correct Answer: (c) QJIR
Solution:

A + 4 = E , E + 4 = I , I + 4 = M , M + 4 = Q
Z - 4 = V , V - 4 = R , R - 4 = N , N - 4 = J
Y - 4 = U , U - 4 = Q , Q - 4 = M , M - 4 = I
B + 4 = F , F + 4 = J , J + 4 = N , N+ 4 = R

5. 3, 15, ?, 63, 99 [RRB NTPC 09/03/2021 (Morning)]

Correct Answer: (b) 35
Solution:

6. 9, 36, 81, ?, 225 [RRB NTPC 09/03/2021 (Morning)]

Correct Answer: (a) 144
Solution:

3² = 9, 6² = 36,9² = 81, 12² = 144, 15² = 225

7. wp, tm , qj, ng, kd,? [RRB NTPC 09/03/2021 (Evening)]

Correct Answer: (c) ha
Solution:

w - 3 = t , t - 3 = q , q - 3 = n , n - 3 = k , k - 3 = h
p - 3 = m ,m - 3 = j , j - 3 = g , g - 3 = d , d - 3 = a

8. 9, 14, 24, 44, ?, 164, 324 [RRB NTPC 09/03/2021 (Evening)]

Correct Answer: (a) 84
Solution:

Logic - 9 + 5 = 14,14 + 10 =24 , 24 + 20 = 44,44 + 40 = 84

9. Find the missing letter/series to complete the following sequence: [RRB NTPC 09/03/2021 (Evening)]

Correct Answer: (d) Q
Solution:

Logic - C + 2 = E , E + 3 = H , H + 4 = L , L + 5 = Q

10. 3 , 7, 16, 35 , ? [RRB NTPC 11/03/2021 (Morning)]

Correct Answer: (d) 74
Solution:

3 × 2 + 1 = 7
7 × 2 + 2 = 16
16 × 2 + 3 = 35
35 × 2 + 4 = 74