Exercise 7.3 - Chapter 7 Information Processing 8th Maths Guide Samacheer Kalvi Solutions - SaraNextGen [2024-2025]

Updated By SaraNextGen

On April 24, 2024, 11:35 AM

Ex $7.3$
Question $1 .$
Fill in the blanks (Use Atbash Cipher that is given in code 3)
Hint
For this question, we need to use Atbash cipher. For Atbash cipher, first we write the alphabets from A to $\mathrm{Z}$ and then in reverse from $Z$ to $A$ below that.
$A B C D E F G H I J K L$ MNOPQRSTUVWXYZ
ZYXW VUTSRQPONMLKJIHGFEDCBA
(i) GZNRO-
Answer:
TAMIL
Hint
Now to solve, we look up the corresponding letter froen the table to replace in code to get the actual word.
So, for G Z N R O, from table,
for $G$, it is $T$
for $Z$, it is $5 /$
for $\mathrm{N}$, it is $\mathrm{M}$
for $\mathrm{R}$, it is $\mathrm{i}$
for 0 , it is $L$
So, the actual word is TAMIL.
(ii) V M TOR HS =
Answer:
ENGLISH
Hint
VMTORHS
To solve, we look up the corresponding letter from table to replace in code to get the actual word.
For V, it is E
for $\mathrm{M}$, it is $\mathrm{N}$
for $T$, it is $G$
for $O$, it is $L$
for $\mathrm{R}$, it is I,
for $\mathrm{H}$, it is $\mathrm{S}$
for $\mathrm{S}$, it is $\mathrm{H}$
Therefore we get E N G L IS H - ENGLISH
(iii) N ZG S V NZGRXH
Answer:
MATHEMATICS

(iv) HXR V M XV
Answer:
SCIENCE
(v) HLXRZOHXRV MXV -
Answer-
SOCIAL SCIENCE

Question $2 .$
Match the following $(a-00 \ldots . . . . . . Z=25)$.
(i) mathematics    (a) 1820011917000219081413
(ii) addition           (b) 0308210818081413
(iii) subtraction      (c) 1200190704120019080218
(iv) multiplication   (d) 0003030819081413
(v) division             (e) 1220111908151115020019081413
Answer:
(i) $-\mathrm{c}$
(ii) - c
(iii) $-\mathrm{a}$
(iv) - $\mathrm{c}$
$(v)-b$

Question $3 .$
Frame Additive cipher table $(k e y=4)$.
Answer:
Step 1 : write all alphabets
Step 2 : Assign numbers to each alphabet starting from 00 till 25 .
Step 3 : add key value (here it is 4 ) to the numbers assigned in step 2 to form cipher table

Question $4 .$
A message like "Good Moming" written in reverse would instead be "Doog Gninrom" In the same way decode the sentence given below:
"Ot dnatsrednu taht scitamehtam nac eb decneirepxe erehwreve ni erutan dna laer efil"
Answer:
Given that good moming written in reverse is doog gninrom.
We have to decode the below by reversing, so,
Ot dnatsrednu taht scitamehtam nac ch decneirepxe erchwreve ni erutan dna lacr efil.
Ans: to understand that mathematics can be experienced everywhere in nature and real life.
 

Question $5 .$
Decode the given Pigpen Cipher text and compare your answer to get result.

Question $6 .$
Praveen recently got the registration number for his new two-wheeler. Here, the number is given in the form of mirror-image. Encode the image and find the correct registration number of praveen's two-wheeler.

Objective Type Questions
Question 7.
In questions (i) and (ii), there are four groups of letters in each set. Three of these sets are alike in some way while one is different. Find the one which is different.
(i).(A) C R D T
(B) A PBQ
(C) EUF V
(D) G W H X
Answer:
(i) (A) C R D T

(ii). (A) $\mathrm{HK} \mathrm{N} \mathrm{Q}$
(B) IL O R
(C) JM MS
(D) A D GJ
Answer:
(D) A D GJ

Question $8 .$
A group of letters are given. A numerical code has been given to each letter. These letters have to be unserambled into a meaningful word. Find out the code for the word so formed from the 4 answers given.
L I NCPE
123456
(A) 234156
(B) 563421
(C) 613524
(D) 421356
Answer:
(B) 563421

Question $9 .$
Questions (iii) and (iv) are based on code language. Find the correct answer from the four alternatives given.
(iii)Inacertain code, 'M E D I C I N E' is coded as 'E O J D J E F M', then how is ' $\mathrm{O} M \mathrm{M} U$ T E R' written in the same code?
(A) C N P V UF Q
(B) CMN Q TUDR
(C) RFI J V Q N C
(D) R N VFTU D Q
Answer:
(C) RFIJ V Q N PC

(iv) If the word 'P H ON E' is coded as 'S KR Q H', how will 'R.A.D I O' be coded?
(A) $\mathrm{SCGNH}$
(B) VRGNG
(C) U D G LR
(D) S D H K Q
Answer:
(C) U D G L R