Number Coding Decoding Tricks: Letter to Number Code and Position Value Questions for SSC

In number coding and decoding, a word is changed into numbers (or numbers into a word) by using the position of letters in the alphabet. You may be asked, "If CAT is 24, what is DOG?" These number coding decoding tricks for SSC explain the position table, the reverse alphabet and the opposite letter code, and give solved examples and practice MCQs.

Alphabet Position Table

Remember EJOTY for the positions 5, 10, 15, 20 and 25. The position of a letter from the right end is 27 minus its position from the left.

Types of Number Codes

Solved Examples

Example 1. If CAT is coded as 24, what is the code of DOG?
CAT = 3 + 1 + 20 = 24, which is the sum of the positions. DOG = 4 + 15 + 7 = 26.

Example 2. If CAB is coded as 312, what is the code of ACE?
A = 1, C = 3 and E = 5, so ACE is 135.

Example 3. What is the opposite letter code of the word CAT?
C (3) is opposite to X (24), A is opposite to Z and T (20) is opposite to G (7). The code is XZG.

Example 4. If 8, 1, 3, 11 stand for letters, which word is made?
8 = H, 1 = A, 3 = C and 11 = K, so the word is HACK.

Example 5. Find the sum of the positions of the letters of the word SSC.
S = 19, S = 19 and C = 3, so the sum is 19 + 19 + 3 = 41.

Tips

• Write the position numbers below the letters before you start.
• Test the rule on the first example word before you use it on the second word.
• If the code is not a sum, try the product, the difference or the reverse order.
• Use the sum of 27 for the opposite letters.

Quick Tips

• Memorise EJOTY (E 5, J 10, O 15, T 20, Y 25).
• Opposite letters add up to 27.
• Write position numbers under the letters.
• Test the rule on the example word first.

Quick Revision Points

• A = 1 and Z = 26.
• The position from the right = 27 minus the position from the left.
• Opposite letter of C is X, because 3 + 24 = 27.
• CAT = 3 + 1 + 20 = 24.
• Test the rule on the example before using it.

Practice Questions With Answers

1. If A = 1, B = 2 and so on, find the sum of the positions of the letters of DOG.
   Answer: 26
2. If A = 1, B = 2 and so on, find the value of BAT.
   Answer: 23
3. If CAB is coded as 312, what is the code of ACE?
   Answer: 135
4. Find the opposite letter code of the word BAT.
   Answer: YZG
5. If 8, 1, 3, 11 stand for letters, which word is made?
   Answer: HACK
6. Find the sum of the positions of the letters of SSC.
   Answer: 41
7. If A = 1, what is the value of Z + A?
   Answer: 27
8. In the reverse alphabet code, what is the value of A?
   Answer: 26
9. Find the product of the positions of the letters of BAD.
   Answer: 8
10. Which letters are at the positions 5, 10, 15, 20 and 25?
    Answer: E, J, O, T, Y

How to Practise This Chapter

Practise 10 questions every day and write the steps on paper. Then attempt timed sets from our practice papers and the previous year papers page. See all topics on the Reasoning notes page, read the previous topic Dice Reasoning and the next topic Reasoning Syllabus and Tricks. Also read Coding-Decoding and Alphabet Test.

Frequently Asked Questions

What is number coding?

It is a code in which letters are changed into numbers, usually by their position in the alphabet.

What is the value of A and Z?

A is 1 and Z is 26 in the normal order, and A is 26 and Z is 1 in the reverse order.

How do I find the opposite letter?

Subtract the position of the letter from 27 and find the letter at that position.

What is the trick to remember letter positions?

Remember EJOTY, which stands for the positions 5, 10, 15, 20 and 25.

How do I decode a number into a word?

Convert each number into the letter at that position.

What if the code is not the sum of the positions?

Try the product, the difference or the reverse order of the letters.

What is the opposite letter of M?

N, because 13 + 14 = 27.

Is number coding asked in SSC exams?

Yes. Coding questions are asked in SSC CGL, CHSL and MTS reasoning papers.

How much time should I take?

About 30 seconds.

What are the common mistakes?

Counting the positions wrongly and not testing the rule on the example.

How can I improve my speed?

Practise the position table for 5 minutes daily.

What is the difference between letter coding and number coding?

Letter coding changes letters into other letters, and number coding changes them into numbers.