Series #1 | Alphabetical Series | Basic Concepts and Types of Questions

What will you learn in this article?

• What are alphabetic series?
• Different types of alphabetic series.
• The Approach towards solving questions in the shortest time.

Exam connect

In these types of question, the examiner gives us a series of letters which follows a definite pattern and we, the examinee has to decipher the pattern used to make the series and then based on it find the answer. The questions from this topic are very common across the spectrum of examinations as it tests out the candidate’s pattern recognition and logical thinking abilities.

Alphabet series

As the name suggests, the questions consist of a series of letters that are arranged in a specific pattern. There are three types of alphabetic series, which are as follows:

1. Positional series

In the positional series, the terms of the series form a certain pattern as per the position of the letters in the English alphabet. 

Example Question: Find the next term in the series: A, C, E, G, ?

Solution: As we can see, the first, second, third letters of the series are moved two places forward to obtain the successive terms of the series.

So the missing term would be two letter ahead of ‘G’ which is ‘I’. Therefore ‘I’ is the missing term in the series.

Common mistakes made: While attempting questions of alphabetical shifting, students try to save up time by trying to find the answer through mental calculations which, can be very inefficient and time-consuming. Hence, it is highly recommended to write down the alphabets first and then search for the pattern.

2. Continuous pattern series

These types of questions consist of a series of letters, which follow a certain pattern within which some letters are missing. Hence, the task of the examinee is to find those omitted letters such that the series start following a prominent pattern.

Eazytip: Instead of directly applying the substitution method, it is recommended to first observe the patterns formed by the adjacent letters and then proceed with the substitution method.

Example Question: Complete the series _a_ba_b_ab

1. abba
2. baab
3. bbab
4. aaab

Solution: Our 1^st step is to find any possible pattern between the consecutive letter which in this case is that ‘a’ is followed by a ‘b’; and also ‘b’ is followed by an ‘a’.

So from that we can say that the first blank should a ‘b’. Now the 3^rd blank could be a ‘a’ so that we can have ‘baab’ or a ‘b’ so that we have the pattern ‘bbabb’. 

So the plausible answers would be ‘baab’ or ‘bbbb’. Since ‘bbbb’ is not given, that means the answer would be 2.

3. Alpha-Numeric series

These types of questions are a mixed form of numeric and alphabetical series. Here, the terms of the given series are a combination of letters and numerals, which move according to a set pattern.

Example Question: Find the next term in the alpha-numeric series:

 A2Z, C3X, E5V, G7T, I11R, K13P, ?

Solution: The patterns followed by the letters are as follows: 

The series formed by the numerals are of prime numbers i.e. 2, 3, 5, 7, 11, 13, 17

So the missing term would be ‘MN17’.