SSC CGL Tier 1 - Reasoning
Topic: Alphabetical Series
EASY LEVEL
Q1. Find the next letter in the series: A, C, E, G, ?
(A) H (B) I (C) J (D) K
Correct Answer: (B) I
Explanation: Step 1: Identify positions → A=1, C=3, E=5, G=7 Step 2: Find the pattern → 1, 3, 5, 7 (each letter increases by +2) Step 3: Next position → 7 + 2 = 9 Step 4: 9th letter = I ∴ The answer is I
Q2. Find the next letter in the series: B, D, F, H, ?
(A) I (B) J (C) K (D) L
Correct Answer: (B) J
Explanation: Step 1: Identify positions → B=2, D=4, F=6, H=8 Step 2: Find the pattern → 2, 4, 6, 8 (each letter increases by +2) Step 3: Next position → 8 + 2 = 10 Step 4: 10th letter = J ∴ The answer is J
Q3. Find the next letter in the series: Z, Y, X, W, ?
(A) U (B) V (C) T (D) S
Correct Answer: (B) V
Explanation: Step 1: Identify positions → Z=26, Y=25, X=24, W=23 Step 2: Find the pattern → 26, 25, 24, 23 (each letter decreases by -1) Step 3: Next position → 23 - 1 = 22 Step 4: 22nd letter = V ∴ The answer is V
Q4. Find the next letter in the series: A, D, G, J, ?
(A) L (B) M (C) N (D) K
Correct Answer: (B) M
Explanation: Step 1: Identify positions → A=1, D=4, G=7, J=10 Step 2: Find the pattern → 1, 4, 7, 10 (each letter increases by +3) Step 3: Next position → 10 + 3 = 13 Step 4: 13th letter = M ∴ The answer is M
Q5. Find the next letter in the series: Z, W, T, Q, ?
(A) N (B) O (C) M (D) P
Correct Answer: (A) N
Explanation: Step 1: Identify positions → Z=26, W=23, T=20, Q=17 Step 2: Find the pattern → 26, 23, 20, 17 (each letter decreases by -3) Step 3: Next position → 17 - 3 = 14 Step 4: 14th letter = N ∴ The answer is N
Q6. Find the next letter in the series: A, E, I, M, ?
(A) P (B) Q (C) R (D) O
Correct Answer: (B) Q
Explanation: Step 1: Identify positions → A=1, E=5, I=9, M=13 Step 2: Find the pattern → 1, 5, 9, 13 (each letter increases by +4) Step 3: Next position → 13 + 4 = 17 Step 4: 17th letter = Q ∴ The answer is Q
Q7. Find the next term in the series: AA, CC, EE, GG, ?
(A) HH (B) II (C) JJ (D) KK
Correct Answer: (B) II
Explanation: Step 1: Identify positions → AA=1, CC=3, EE=5, GG=7 Step 2: Find the pattern → Both letters are same and increase by +2 Step 3: Next position → 7 + 2 = 9 Step 4: 9th letter = I, so the pair = II ∴ The answer is II
MEDIUM LEVEL
Q8. Find the next letter in the series: A, B, D, G, K, ?
(A) N (B) O (C) P (D) Q
Correct Answer: (C) P
Explanation: Step 1: Identify positions → A=1, B=2, D=4, G=7, K=11 Step 2: Find differences → 2-1=1, 4-2=2, 7-4=3, 11-7=4 Step 3: Pattern → Differences are increasing: +1, +2, +3, +4, +5 Step 4: Next position → 11 + 5 = 16 Step 5: 16th letter = P ∴ The answer is P
Q9. Find the next letter in the series: B, D, G, K, ?
(A) O (B) P (C) Q (D) R
Correct Answer: (B) P
Explanation: Step 1: Identify positions → B=2, D=4, G=7, K=11 Step 2: Find differences → 4-2=2, 7-4=3, 11-7=4 Step 3: Pattern → Differences are increasing: +2, +3, +4, +5 Step 4: Next position → 11 + 5 = 16 Step 5: 16th letter = P ∴ The answer is P
Q10. Find the next letter in the series: A, Z, B, Y, C, ?
(A) D (B) X (C) W (D) E
Correct Answer: (B) X
Explanation: Step 1: Identify two alternating patterns:
Series 1 (odd positions): A, B, C → Forward from A (+1)
Series 2 (even positions): Z, Y, ? → Backward from Z (-1) Step 2: The 6th position belongs to Series 2 Step 3: Pattern in Series 2 → Z=26, Y=25, next = 24 Step 4: 24th letter = X ∴ The answer is X
Q11. Find the next term in the series: AB, DE, GH, JK, ?
(A) LM (B) MN (C) NO (D) OP
Correct Answer: (B) MN
Explanation: Step 1: Identify first letters → A=1, D=4, G=7, J=10 (pattern: +3) Step 2: Identify second letters → B=2, E=5, H=8, K=11 (pattern: +3) Step 3: Next first letter → 10 + 3 = 13 = M Step 4: Next second letter → 11 + 3 = 14 = N ∴ The answer is MN
Q12. Find the next term in the series: AC, EG, IK, MO, ?
(A) PR (B) QS (C) RT (D) SU
Correct Answer: (B) QS
Explanation: Step 1: Identify first letters → A=1, E=5, I=9, M=13 (pattern: +4) Step 2: Identify second letters → C=3, G=7, K=11, O=15 (pattern: +4) Step 3: Next first letter → 13 + 4 = 17 = Q Step 4: Next second letter → 15 + 4 = 19 = S ∴ The answer is QS
Q13. Find the next letter in the series: A, B, D, E, G, H, ?
(A) I (B) J (C) K (D) L
Correct Answer: (B) J
Explanation: Step 1: Identify positions → A=1, B=2, D=4, E=5, G=7, H=8 Step 2: Find differences → 1, 2, 1, 2, 1 Step 3: Pattern → Alternating +1, +2, +1, +2, +1, +2 Step 4: Next difference is +2 → 8 + 2 = 10 Step 5: 10th letter = J ∴ The answer is J
Q14. Find the next letter in the series: Z, Y, W, T, P, ?
(A) K (B) L (C) J (D) I
Correct Answer: (A) K
Explanation: Step 1: Identify positions → Z=26, Y=25, W=23, T=20, P=16 Step 2: Find differences → 26-25=1, 25-23=2, 23-20=3, 20-16=4 Step 3: Pattern → Differences are increasing: -1, -2, -3, -4, -5 Step 4: Next position → 16 - 5 = 11 Step 5: 11th letter = K ∴ The answer is K
HARD LEVEL
Q15. Find the next letter in the series: A, C, F, J, O, ?
(A) T (B) U (C) V (D) S
Correct Answer: (B) U
Explanation: Step 1: Identify positions → A=1, C=3, F=6, J=10, O=15 Step 2: Find differences → 3-1=2, 6-3=3, 10-6=4, 15-10=5 Step 3: Pattern → Differences are increasing: +2, +3, +4, +5, +6 Step 4: Next position → 15 + 6 = 21 Step 5: 21st letter = U ∴ The answer is U
Q16. Find the next letter in the series: A, Z, C, X, E, ?
(A) V (B) W (C) U (D) G
Correct Answer: (A) V
Explanation: Step 1: Identify two alternating patterns:
Series 1 (odd positions): A=1, C=3, E=5 → Pattern: +2 (forward)
Series 2 (even positions): Z=26, X=24, ? → Pattern: -2 (backward) Step 2: The 6th position belongs to Series 2 Step 3: Next in Series 2 → 24 - 2 = 22 Step 4: 22nd letter = V ∴ The answer is V
Q17. Find the next term in the series: ABC, EFG, IJK, ?
(A) MNO (B) NOP (C) LMN (D) OPQ
Correct Answer: (A) MNO
Explanation: Step 1: Identify first letters → A=1, E=5, I=9 (pattern: +4) Step 2: Each group has 3 consecutive letters Step 3: Next first letter → 9 + 4 = 13 = M Step 4: Consecutive letters after M → M, N, O ∴ The answer is MNO
Q18. Find the next term in the series: AZ, CX, EV, GT, ?
(A) IR (B) IS (C) HR (D) HS
Correct Answer: (A) IR
Explanation: Step 1: Identify first letters → A=1, C=3, E=5, G=7 (pattern: +2) Step 2: Identify second letters → Z=26, X=24, V=22, T=20 (pattern: -2) Step 3: Next first letter → 7 + 2 = 9 = I Step 4: Next second letter → 20 - 2 = 18 = R ∴ The answer is IR
Q19. Find the next letter in the series: A, B, C, E, H, ?
(A) L (B) M (C) N (D) K
Correct Answer: (B) M
Explanation: Step 1: Identify positions → A=1, B=2, C=3, E=5, H=8 Step 2: Find differences → 2-1=1, 3-2=1, 5-3=2, 8-5=3 Step 3: Pattern → Fibonacci-like: 1, 1, 2, 3, 5 (each difference = sum of previous two) Step 4: Next difference → 3 + 2 = 5 Step 5: Next position → 8 + 5 = 13 Step 6: 13th letter = M ∴ The answer is M
Q20. Find the next term in the series: ZA, YB, XC, WD, ?
(A) VE (B) UE (C) VF (D) UF
Correct Answer: (A) VE
Explanation: Step 1: Identify first letters → Z=26, Y=25, X=24, W=23 (pattern: -1, backward) Step 2: Identify second letters → A=1, B=2, C=3, D=4 (pattern: +1, forward) Step 3: Next first letter → 23 - 1 = 22 = V Step 4: Next second letter → 4 + 1 = 5 = E ∴ The answer is VE