## Coding Decoding

Coding is the method of transforming the characters in such a way that no third person can understand it.

Some Tips to Remember the Opposite Alphabets.

### Types of Coding

Letter Coding
In letter coding, letters are coded in letters by using different pattern and sequence

Example-1- In a certain language, BUTTER is coded as CVUUFS, BREAD is coded as CSFBE, then how COFFEE is coded?
(1) DPGGFF
(2) GGDPFF
(3) GDPGFF
(4) FFDPGG
Solution:-

Example-2- In a coding system PEN is written as NZO and BARK as CTSL. How can we write PRANK in that coding system?
(1) NZTOL
(2) CSTZN
(3) NSTOL
(4) NTSLO
Solution:-

Number Coding
In number coding letters are coded in numbers by using different pattern and sequence.

Example-3- If BROTHER is coded as 2456784. SISTER is coded as 919684, what is the code for ROBBERS?
(1) 18, 15, 22, 5, 18, 19
(2) 4562 684
(3) 9245 784
(4) 4522849
Solution:-

Ex. In a certain code language 'LIEUTENANT' is written as 1232212021411420,then how 'MANGO' can be written in that code language?
(a) 13114715
(b) 1311474
(c) 14141375
(d) 13114157
Solution:- Code for Consonant is it's place value, and code for vowels are given below
A ⇒ 1,
E ⇒ 2,
I ⇒ 3,
O ⇒ 4,
U ⇒ 5
Therefor
M ⇒ 13,
A ⇒ 1,
N ⇒ 14,
G ⇒ 7,
O ⇒ 4
So the code for MANGO is 1311474

Conditional Coding
In conditional coding, few conditions are given in the question, we have to follow the some to code the characters.

Ex- In each question below is given a group of letters followed by four combinations of numbers numbered (1), (2), (3) and (4). You have to find out which of the combinations correctly represents the group of letters based on the following coding system and conditions that follow and mark the number of that combination as your answer. If none of the combinations correctly represents the group of letters, mark (5) i.e. ‘None of these’ as your answer.

 Letters Numbers A B C D E F G H I J K L M 1 2 3 4 5 6 8 7 9 11 10 13 12

Conditions:
(Ⅰ) If the first and last letter’s place values according to English alphabetical order has difference of 1 then both are to be coded by the code of G.
(Ⅱ) If the first letter is a vowel and last letter is a consonant then the code of both are to be interchanged.
(Ⅲ)If fourth letter’s place value is multiple of 3 then the second letter is to be coded by the code of six letter.

Ex- CBJIKM
(1) 3 2 11 19 12
(2) 31112291
(3) 31219112
(4) 312119102
(5) None of these
Solution:- According to Condition Ⅲ
None of these

Ex- EFGMJA
(1) 5671111
(2) 5671411
(3) 5116711
(4) 5617111
( 5) None of these
Solution:- According to Condition
None of these

Substitution Coding
In substitution coding, one word is replaced by another word, rather than coding in a sequence.

Ex- In a certain code language '481' means 'sky is blue', '246' means 'sea is deep' and '698' means 'sea looks blue'. What number is the code for 'blue'.
(a) 8 (b) 6 (c) 1 (d) 9
Solution:- '481' means 'sky is blue' ……(ⅰ)
'246' means 'sea is deep' ………….(ⅱ)
'698' means 'sea looks blue' ………………(ⅲ)
From ⅰ and ⅲ 8 and blue is common.
∴ Code of blue = 8

Ex. In a certain code,SOBER is written as RNAD. How LOTUS can be written in that code?
(a) KNSTR
(b) MPUWT
(c) KMSTR
(d) LMRST
Solution:- K comes before L
N comes before O
S comes before T
T comes before U
R comes before S
This way KNSTR is correct option

Ex. If 16 - 2 = 2, 9 - 3 = 0, 81 - 1 = 8, then what is 64 - 4 ?
(a) 4
(b) 2
(c) 6
(d) 8
Solution:- Correct Option (a)
16 ⇒ (2 + 2)2 = 42
9 ⇒ (3 + 0)2 = 32
∴ 64 ⇒ (4 + 4)2 = 82