# Reasoning Coding and decoding

Coding means to hide the meaning of any message and decoding means to understand the actual meaning of that message.

Coding is a method of transmitting a message between the sender and the receiver that no third person can understand it. The coding and decoding one’s ability of deciphering the rule and breaking the code to decipher the message will be tested to know.

Approach:

1. Observe alphabets or numbers given in the code keenly.
2. Find the sequence it follows whether it is ascending or descending.
3. Detect the rule in which the alphabets/numbers/words follow.
4. Fill the appropriate letter/number/word in the blank given.

In questions based on coding-decoding, a word or sentence is coded in a particular way and the candidates are asked to code other word or sentence in the same way or to decode the word or sentence.

To solve these questions, the candidates are required to understand the rule that has been followed to code a particular word or message.

### Position of letters in English Alphabet

Sometimes a word or a sentence is coded by changing the position of English Alphabet letters according to a definite pattern, so it is necessary to remember the positions of all the letters in English alphabetical order, both in forward and backward order.

### Order of the English Alphabet

 Forward Order Position Letters Backward Order Position 7 G 20 8 H 19 9 I 18 10 J 17 11 K 16 12 L 15 13 M 14 14 N 13 15 O 12 16 P 11 17 Q 10 18 R 9 19 S 8 20 T 7 21 U 6 22 V 5 23 W 4 24 X 3 25 Y 2 26 z 1

Letter coding: Alphabets in a word are replaced by other alphabets according to a specific rule to know its code. So the common rule should detected first. Some examples are given below:

1)‘ZYXW’ as coded as ‘ABCD’ then ‘STUV’ is coded as...........

Answer:Z – A, Y– B, X – C, W – D V – E, U – F, T – G, S – H STUV = HGFE Answer = HGFE Rule= front alphabet= back alphabet.

2) ‘ bcd’ is coded as ‘def’ then ‘True’ is coded as..........

Answer:Answer: b – d (+2) c – e (+2) d – f (+2) +2 letters are considered in this code. True – Vtwg Answer = Vtwg.

3) ‘ Hyderabad ’ is coded as ‘Ixedszcze’ then ‘Chennai’ is coded as..............

Answer:H – I (+1) Y – X (1–) D – E (1+) E – D (1-) R – S (1+) A – Z (1–) B – C (1+) A – Z (1– ) D – E (1+) Here if we observe alternatively the letter increasing and one letter decreasing. Chennai =dgfmozj Answer = dgfmozj

Number coding: In this each alphabets or words are assigned to the numeric values we should observe the given letters and the assigned values and use the same rule to find the value to of given code. Some examples are given below:

1)Apple is coded as 25563, Rung is coded as 7148. Then purple is coded as

2)In a language A is coded as 1, B is coded as 2, ….. then FACE is coded as

Answer:Then FACE = 6135 Answer = 6135.

3)PUSH is coded as 1234, ROUGH is coded as 65274. Then SOUP is coded as

### Types of coding - Decoding:

Type-1 : Letter/Number coding

In this type of coding, we deal with questions, in which the letters of a word are replaced by certain other letters or numbers according to a specific pattern/rule to form a code. You are required to detect the coding pattern / rule and answer the questions that are asked, based on that coding pattern / rule.

Type-2 : Direct coding

In direct coding, the code letters/numbers/symbols occur in the same sequence as the corresponding letters occur in the words. This is basically a direct substitution method

Type-3 : Fictitious language coding

Here, coded form of two or more sentences is given and you are required to find the code of a particular word or message.

To analyse such codes, any two messages bearing a common word/number are picked up. The common code will represent that particular word/number.

To analyse such codes, any two messages bearing a common word/number are picked up. The common code will represent that particular word/number.

Proceeding similarly by picking up all possible combinations of two, the entire message can be decoded and the codes for every individual word/number can be found.

In some cases, there is no common word/number in the message given. In those cases, the words/numbers are coded separately. You have to identify the correct pattern of coding and find the code for the word or message given in the question.

Type-4 : Substitution coding

In this type of coding, some particular words are coded with certain substituted word and on the basis of substituted word, the code of given word is derived.

##### 1. In a certain code 'MISSIONS' is written as 'MSIISNOS'. How is 'ONLINE' written in that code?

A) OLNNIE

B) ONILEN

C) NOILEN

D) LNOENI

Explanation: First and last letter remain same. The others interchange their positions in pair of two. So, NL become LN IN become NI so code of ONLINE will be OLNNIE.

##### 2. In certain code 'TIGER' is written as 'QDFHS'. How is 'FISH' written in that code?

A) GERH

B) GRHE

C) GREH

D) GHRE

Explanation: Reverse the word and move each letter –1. Reverse of FISH is HSIF subtract 1 from each letter of HSIF. So code of FISH become GRHE.

##### 3. In certain code 'FROZEN' is written as 'OFAPSG'. Then how would 'MOLTEN' be written in that code?

A) OFPOMN

B) OFSMPN

C) OFUMPN

D) OFUNPM

Explanation: Reverse the word and move each letter +1. Reverse of MOLTEN is NETLOM add 1 to each letter of NETLOM. So code of MOLTEN become OFUMPN.

##### 4. In a certain code 'ROAR' is written as 'URDU'. How is 'URDU' written in that code?

A) VXDQ

B) XUGX

C) ROAR

D) VSOV

Explanation: Each letter moves +3. Add 3 to each letter of URDU,so code of URDU will be XUGX.

##### 5.In a certain code 'LIMCA' is written as 'HJLDZ'. Which of the following words is written as 'IFWJBP'?

A) MEXICO

B) MERCURY

C) JAPAN

D) MIDNIGHT

Explanation:Each letter moves +1, -1, ....alternately except for L, which is –4. We have to find the word for the code IFWJBP. Add 4 to I then -1, +1 alternately to the remaining letters. The word will be MEXICO.

##### 6.In certain code 'HILTON' is written as 'IHTLNO'. How is 'BILLION' written in that code?

A) IBLLION

B) IBOILLN

C) IBLLOIN

D) IBLOILN

Explanation: Letters are interchanged in each pair. So code of BI become IB, IO become OI. So code BILLION will be IBLLOIN.

##### 7.If in the English alphabet, every alternate letter from B onwards is written in small letters while others are written in capitals, then how will the 3rd day from Tuesday will be coded?

A) W e D N e S d A Y

B) W E d n E S d A Y

C) T h U r S d A Y

D) f r I d A Y

Answer:D) f r I d A Y

Explanation: The small letters are b, d, f, h, j, l, n, p, r, t, v, x, z. The third day from tuesday will be friday and code will be frIdAY.

##### 8.If the letters of the word 'CYCLINDER' are arranged alphabetically, then which letter would be farthest from the first letter of word?

A) N

B) E

C) Y

D) R

Explanation: Last letter is ‘Y’.

##### 9.In a certain code 'CERTAIN' is coded as 'BFQUZJM'. How is 'MUNDANE' coded in that code?

A) LVMEZOD

B) NTCOMBF

C) NTOCNBF

D) LTMCZOF

Explanation: Each letter moves -1, +1 alternately. So, M - 1 = L, U + 1 = V and so on. So code for MUNDANE will be LVMEZOD.

##### 10.In a certain code 'SEQUENCE' is coded as 'FDOFVRFT. How is 'CHILDREN' coded in that code?

A) OFESJMID

B) OFSEMJID

C) OFSEJIMD

D) OFSEJMID

Explanation: Reverse the word and +1 to each letter. The reverse of CHILDREN is NERDLIHC. add 1 to each letter. Therefore, the code of CHILDREN becomes OFSEMJID.

##### 11.In a certain code ‘RATIONAL’ is written as ‘TARNOILA’. How would ‘BRUTAL’ be written in that code?

A) UBRTAL

B) URBLAT

C) UBRATL

D) URBTAL

Explanation:Letters are reversed in groups of 3 which can be shown as: RAT = TAR, ION = NOI. etc. So for BRUTAL BRU = UBR TAL = LAT so code for BRUTAL = UBRLAT.

##### 12.In a certain code ‘PURPOSE’ is written as ‘UPPRSOE’. How would ‘WATER’ be written in that code?

A) WATRE

B) AWTRE

C) AWETR

D) WEATR

Explanation: Interchange the letter in the pair of two and keep the last letter as it is. WA = AW TE = ET So code of WATER is AWETR.

##### 13.In a certain code ‘FORGIVE’ is written as ‘DPPHGWC’. How would ‘REQUEST’ be written in that code?

A) PFOVCUR

B) TFOVCRU

C) POFCVUR

D) PFOVCTR

Explanation: The letters move –2, +1, alternately R-2=P, E+1=F, Q-2=O, U+1=V and so on. So code of REQUEST is PFOVCTR.

##### 14.If CALM is written as HEOO , YEAR may be written as

A) DHDS

B) DTDH

C) DDHT

D) DIDT

Explanation: Each letter moves +5, +4, +3, +2. Therefore, ‘DIDT’ is a code for ‘YEAR’.

##### 15.If CALM is written as XZON, YEAR may be written as

A) BVZI

B) BZVI

C) BVIZBVZJ

D) BVZJ

Explanation: The concept of Reverse EJOTY is followed. Or we can also say that sum of letter & its respective coded letter is 27. Y+B=25+2=27, E+V=5+22=27, and so on. Hence code for YEAR is ‘BVZI’.

##### 16.If CALM is written as LKZB, YEAR may be written as

A) BQDX

B) QZNX

C) QZDX

D) QDBX

Explanation:Letters are reversed and then move –1. Reverse of YEAR is RAEY and subtract 1 from each letter. Hence Code for YEAR is ‘QZDX’.

##### 17.If CALM is written as AYJK, YEAR may be written as

A) WCYP

B) WCXP

C) CWXP

D) PWXY

Explanation:Each letter moves –2. Y-2=W, E-2=C and so on. therefore, code for YEAR is ‘WCYP’.

##### 18.If CALM written as ZDIP, YEAR may be written as

A) ZXHV

B) HVXZ

C) VHXU

D) VHWZ

Explanation: The letters move –3, +3, alternately Y-3=V, E+3=H and so on. Hence code for YEAR is ‘VHXU’.

##### 19.In a certain code ‘EASIER’ is written as TGKUCG. How is CUTTER written in that code?

A) TWVVGE

B) TGWWVE

C) TGVVWE

D) TVGVWE

Explanation:Letters are written in reverse and move +2. Reverse of CUTTER is RETTUC. Now add 2 to each letter R+2=T, E+2=G, T+2=V and so on. So code of CUTTER is TGVVWE.

##### 20.If ‘MEANDER’ is coded as ‘4515459’, then ‘MATHEMATICS’ is coded as

A) 6 7 2 5 0 6 2 3 0 7 6

B) 4 1 2 8 5 4 1 2 9 3 1

C) 4 5 0 3 8 4 0 1 8 5 4

D) 5 7 1 5 9 4 1 3 9 5 5

Answer:B) 4 1 2 8 5 4 1 2 9 3 1

Explanation: Letters are arranged according to the digital sum roots which is explained by Example: A = 1, B = 2, ..... ,H=8, I = 9, J = 10=1+0=1,M= 13= 1+3=4 & so on. Similarly, code for MATHEMATICS is 4 1 2 8 5 4 1 2 9 3 1.

##### 21.In a certain code language COMPUTER is written as RFUVQNPC. How will MEDICINE be written in that code language?

A) MFEDJJOE

B) EOJDEJFM

C) MFEJDJOE

D) EOJDJEFM

Explanation:- There are 8 letters in the word. - There are 8 letters in the word. - The coded word can be obtained by taking the immediately following letters of word, expect the first and the last letters of the given word but in the reverse order. That means, in the coded form the first and the last letters have been interchanged while the remaining letters are coded by taking their immediate next letters in the reverse order.

##### 22.In a certain code language, '134' means 'good and tasty'; '478' means 'see good pictures' and '729' means 'pictures are faint'. Which of the following digits stands for 'see'?

A) 9

B) 2

C) 1

D) 8

Explanation:Justification: In the first and second statements, the common code digit is '4' and the common word is 'good'. So, '4' stands for 'good'. In the second and third statements, the common code digit is '7' and the common word is 'pictures'. So, '7' means 'pictures'. Thus, in the second statements, '8' means 'see'.

##### 23.In a certain code, MONKEY is written as XDJMNL. How is TIGER written in that code ?

A) SHFDQ

B) HFDSQ

C) RSAFD

D) QDFHS

Explanation: The letter of the word are written in a reverse order and then each letter is moved one step backward to obtain the code.

##### 24.If ROSE is coded as 6821, CHAIR is coded as 73456 and PREACH is coded as 961473, what will be the code for SEARCH ?

A) 246173

B) 214673

C) 214763

D) 216473

Explanation: The alphabets are coded as shown : R O S E C H A I P6 8 2 1 7 3 4 5 9 So, in SEARCH, S ia coded as 2, E as 1, A as 4, R as 6, C as 7, H as 3. Thus, the code for SEARCH is 214673.

A) 39

B) 41

C) 44

D) 46