Introduction & Examples: Letter Series - CSAT Preparation - UPSC

Introduction

• From the above diagram, you can easily see the position and opposite word of each alphabet.
  Example: Position of D is 4 and opposite letter to D is W and position of W is 23.
• Position of J is 10 and opposite letter of J is Q and position of Q is 17 and so on

Examples

Find the letter in place of the question mark (?) in the series given below:

Q1. B, F, ?, N, R

a) G

b) K

c) J

d) L

e) None of The Above

Ans: Option C

Q2. P, ?, J, G, D, A

a) Q

b) N

c) K

d) M

e) None of The Above

Ans: Option D

Q3. ?, E, G, J, N

a) A   

b) B

c) D

d) Z

e) None of The Above

Ans: Option C

Q4. X, F, Y, G, ?, H

a) Z

b) A

c) B

d) Y

e) None of The Above

Ans: Option A

Q5. B, B, A, D, ?, F    

a) B

b) A

c) Z

d) C

e) None of The Above 

Ans: Option C

1. SCD, TEF, UGH, ____, WKL

A.   CMN

B.   UJI

C.   VIJ

D.   IJT

Answer: C

Explanation: There are two alphabetical series here. The first series is with the first letters only: STUVW. The second series involves the remaining letters: CD, EF, GH, IJ, KL. 

Q.7. B₂CD, _____, BCD₄, B₅CD, BC₆D

A.    B₂C₂D

B.    BC₃D

C.    B₂C₃D

D.    BCD₇

Answer: Option B

Explanation: Because the letters are the same, concentrate on the number series, which is a simple 2, 3, 4, 5, 6 series, and follows each letter in order. 

Q.8. FAG, GAF, HAI, IAH, ____

A.    JAK

B.    HAL

C.    HAK

D.    JAI

Answer: Option A

Explanation: The middle letters are static, so concentrate on the first and third letters. The series involves an alphabetical order with a reversal of the letters. The first letters are in alphabetical order: F, G, H, I , J. The second and fourth segments are reversals of the first and third segments. The missing segment begins with a new letter.

Q.9. ELFA, GLHA, ILJA, _____, MLNA

A.    OLPA

B.    KLMA

C.    LLMA

D.    KLLA

Answer: Option D

Explanation: The second and fourth letters in the series, L and A, are static. The first and third letters consist of an alphabetical order beginning with the letter E.

Q.10. CMM, EOO, GQQ, _____, KUU 

A.    GRR

B.    GSS

C.    ISS

D.    ITT

Answer: Option C

Explanation: The first letters are in alphabetical order with a letter skipped in between each segment: C, E, G, I, K. The second and third letters are repeated; they are also in order with a skipped letter: M, O, Q, S, U.

Q.11. BCB, DED, FGF, HIH, ___

A.    JKJ

B.    HJH

C.    IJI

D.    JHJ

Answer: Option A

Explanation: This series consists of a simple alphabetical order with the first two letters of all segments: B, C, D, E, F, G, H, I, J, K. The third letter of each segment is a repetition of the first letter.

Q.12. QAR, RAS, SAT, TAU, _____

A.    UAV

B.    UAT

C.    TAS

D.    TAT

Answer: Option A

Explanation: In this series, the third letter is repeated as the first letter of the next segment. The middle letter, A, remains static. The third letters are in alphabetical order, beginning with R.