How to Solve Coding - Decoding? Concept & Tips
Types of coding and decoding:
Type 1: Letter coding:In this type the real alphabets in a word are replaced by certain other alphabets according to the specific rule to form its code.
Case 1:Form the code for another wordIf in a certain language NZTUJGZ is coded as OAUVKHA.how is OFNFTJT coded in that language?
Sol: Clearly,each letter
NZTUJGZ +1 -> OAUVKHA
So, in OFNFTJT ,O will be coded as P ,F as G,N as O,F as G,T as U and so on.Thus the code OFNFTJT become s
PGOGUKU.
If in a certain code CHESS is coded as BGDRR,which word will be coded as MOUSE?
Sol:Each letter of the word is one step ahead of the corresponding letter of the code
BGDRR +1->CHESS
so,M is coded as N,O as P,U as V,S as T,E as F.Therefore,MOUSE is coded as NPVTF.
In this type either numerical code values are assigned to a word or alphabetical code letters are assigned to the numbers.
Case 1:If numerical code values are assigned to words:If in a certain language A is coded as 1,B is coded as 2 and so on.How is LOGICAL is coded in that code?
sol:
As given the letters are coded as
A B C D E F G as 1 2 3 4 5 6 7
So in LOGICAL,L is coded as 12,O is coded as 15,G as 7 and so on.
Thus LOGICAL is coded as 1215793112.
In a certain code,2 is coded as P,3 as N ,9 as Q ,5 as R,4 as A and 6 as B.How is 599423 coded in that code?
sol:Clearly as given 5 is coded as R,9 as Q,4 as A,2 as P,3 as N.
so,599423 is coded as RQQAPN.
Type 3:Substitution
In this type object names are substituted with different object names.We should carefully trace the substitution and
answer them.
For eg:If white is called blue,blue is called red,red is called yellow,yellow is called green,green is called black ,black is
called violet and violet is called orange ,what would be the color of human blood?
Sol:The color of the human blood is red and as it is given that red is called 'yellow'.so,the color of the human blood is
'yellow'.
In this type either alphabetical code values are assigned to symbols or symbols are assigned to alphabets.
For eg:
In a certain code 'PAIR' is written as '!@#$' and ARE is written as '!$%' .How can 'REPAIR' be written in that code?
Sol:From the data we have P-!,A-@,I-# and R-$
Hence REPAIR is coded as $%!@#$
In this type ,3 or 4 complete messages are given in the coded language and the code for a particular word is asked.To analyze such codes,any two messages bearing a common word are picked up.The common code word will mean that word.Proceeding similarly by picking up all possible combinations of two,the entire messages can be analysed.
For example:In a certain code language,
1.'pod na joc' means 'very bright boy'
2.'tam nu pod' means 'the boy comes';
3.'nu per ton' means 'keep the doll';
4.'joc ton su' means 'very good doll';
Which of the following means 'bright' in the same code language?
a.joc b.pod c.ton d.na
Ans:D
In statements 1 and 2 the common code word is 'pod' and the common word is 'boy'.
so,'pod' stands for 'boy'.
In statements 1 and 4 ,the common code word is 'joc' and the common word is 'very'.
So,'joc' stands for 'very'
so in 1 'na' stands for 'bright'.
In this type of questions ,a few groups of numbers each coding a certain short messages,are given .Through a comparison of the given coded mesages,taking two at a time,the candidate is required to find the number code for each word and then formulate the code for the message given.
For example:In a certain code,
'786' means 'study very hard';
'958' means 'hard work pays';
'645' means 'study and work';
Which of the following is the code for 'very'?
a.7 b.5 c.8 d.6
Ans a.7
In the first and second statements ,the common word is 'hard' and the common code digit is '8'.so 8 means 'hard'. In the first and third statements ,the common word is 'study' and the common code digit is '6'.so '6' means 'study'. Thus in the first statement '7' means 'very'
Some useful Tricks:Tip 1:Use EJOTY to remember position of alphabet (Total-26)in series
There are exactly 26 letters in English alphabets.
A-Z- (1 to 26),
A-1,
B-2;
C-3, … and so on.
We should learn numbering of every letter. So for better convenience, you can learn two words which help you to remember numbering of letters which are given below:
5 10 15 20 25
E J O T Y
Reverse EJOTY:
When we start count Alphabets from the Z to A, this is called reverse EJOTY.
It can be easily explained by an example given below:
Example:
If code for AYNA is ‘ZBMZ’, find the code for NUTS.
According to alphabet series, the position of A-1 , Y-25, N-14, A-1
In reverse EJOTY, Z-1, B-25, M- 14, Z-1
Or we can also say that,
1 25 14 1
A Y N A
+
Z B M Z
26 2 13 26
Sum of every letter & its corresponding coded letter is 27. Therefore, code for NUTS is ‘MFGH’