Introduction

This guide covers the Series Completion topic for All Exams aspirants. Master the concept, understand the tricks, and then test yourself with 10 practice MCQs.

Series Completion — Concept Guide

Series completion questions present a sequence of letters, numbers, or letter-number combinations and ask you to find the next term(s) or fill in the missing one.

Types of Series

  • Alphabetical: Forward (A,C,E...) or backward (Z,X,V...)
  • Skipping: Every alternate letter, every 3rd letter, etc.
  • Paired: AB, CD, EF... or AZ, BY, CX... (one goes forward, one backward)
  • Numeric embedded: A1B, C2D, E3F...
  • Repetition: A, BB, CCC, DDDD...

Approach

  1. Find position of each letter in the alphabet (EJOTY trick: E=5, J=10, O=15, T=20, Y=25).
  2. Calculate differences between positions.
  3. Check if numbers follow arithmetic/geometric pattern.

⚡ Shortcuts & Tricks

  • Write the alphabet with numbers (A=1 to Z=26) quickly on your rough sheet.
  • Use EJOTY as anchor points for fast position finding.
  • When series has paired elements (letter + number), track each separately.
  • For reverse series: position from end = 27 - position from start.
  • Common gaps: +2 (every alternate), +4 (skip 3), +5 (ABCDE skip to FGHIJ).

Practice MCQs — Series Completion (10 Questions)

Now test your understanding with these 10 questions:

Q1. AB, BC, CD, DE, __?

  • A. EF
  • B. FF
  • C. FG
  • D. EE
Answer: A — Consecutive letter pairs shifting by 1.

Q2. Z, X, V, T, __?

  • A. R
  • B. S
  • C. Q
  • D. P
Answer: A — Every alternate letter backwards. T-2=R.

Q3. A, C, F, J, O, __?

  • A. U
  • B. T
  • C. V
  • D. W
Answer: A — Gaps: +2,+3,+4,+5,+6. O+6=U.

Q4. AZ, BY, CX, DW, __?

  • A. EV
  • B. FW
  • C. EU
  • D. EX
Answer: A — First letters A,B,C,D,E; second letters Z,Y,X,W,V.

Q5. 1A, 2B, 3C, 4D, __?

  • A. 5E
  • B. 4E
  • C. 6F
  • D. 5D
Answer: A — Number and letter both increment by 1.

Q6. AB, EF, IJ, MN, __?

  • A. QR
  • B. OP
  • C. PQ
  • D. RS
Answer: A — Gaps of 4 between pairs: AB,EF,IJ,MN,QR.

Q7. ACE, BDF, CEG, DFH, __?

  • A. EGI
  • B. FHI
  • C. EHJ
  • D. EGJ
Answer: A — Each trio shifts by 1: A+1=B,C+1=D,E+1=F... → EGI.

Q8. Z, Y, X, W, V, U, __?

  • A. T
  • B. S
  • C. R
  • D. Q
Answer: A — Alphabet backwards, one at a time.

Q9. ABA, BCB, CDC, DED, __?

  • A. EFE
  • B. EEF
  • C. FEF
  • D. EFF
Answer: A — Pattern ABA→BCB: outer letters move forward by 1, inner by 1.

Q10. 2Z, 4Y, 6X, 8W, __?

  • A. 10V
  • B. 10W
  • C. 9V
  • D. 10U
Answer: A — Numbers +2; letters -1. 10V.

Summary

Series Completion is a scoring topic in All Exams if you practise consistently. Focus on understanding the concept, apply the shortcut tricks, and practice regularly. Aim for 100% accuracy in this topic through regular revision.