This IELTS Reading post focuses on all the solutions for IELTS Cambridge 9 Test 3 Reading Passage 3 which is entitled ‘Information theory – the big idea‘ . This is a post for candidates who have major problems in finding Reading Answers. This post can guide you the best to comprehend each Reading answer without facing much difficulty. Tracing IELTS Reading answers is a slow process and I sincerely hope this post can assist you in your IELTS Reading preparation.

IELTS Cambridge 9 Test 3: AC Reading Module

Reading Passage 3:

The headline of the passage: Information theory – the big idea

Questions 27-32   (Identifying information):

[This question asks you to find information from the passage and write the number of the paragraph (A, B, C or D … .. ) in the answer sheet. Now, if the question is given in the very first part of the question set, I’d request you not to answer them. It’s mainly because this question will not follow any sequence, and so it will surely kill your time. Rather, you should answer all the other questions first. And just like List of Headings, only read the first two lines or last two lines of the expected paragraph initially. If you find the answers, you need not read the middle part. If you don’t find answers yet, you can skim the middle part of the paragraph. Keywords will be a useful matter here.]

Question 27: an explanation of the factors affecting the transmission of information.

Keywords for this question: factors affecting, transmission of information,

Paragraph D has the answer for this question. In lines 1-5 the writer says, “Noise usually means unwanted sounds which interfere with genuine information. Information theory generalises this idea via theorems that capture the effects of noise with mathematical precision. In particular, Shannon showed that noise sets a limit on the rate at which information can pass along communication channels while remaining error-free… .. .”

Here, transmission = pass along communication channels

So, the lines suggest that factors such as noise can affect transmission of information.

So, the answer is: D

Question 28: an example of how unnecessary information can be omitted

Keywords for this question: unnecessary information, omitted,

This question’s answer is found in paragraph F where the author talks about the solution of excluding unwanted information. In lines 1-4 the author states, “Shannon also laid the foundations of more efficient ways of storing information, by stripping out superfluous (redundant) bits from data which contributed little real information. As mobile phone text messages like ‘I CN C U’ show, it is often possible to leave out a lot of data without losing much meaning.”

Here, stripping out superfluous (redundant) bits from data & to leave out a lot of data means unnecessary data or information can be omitted.

So, the answer is: F

Question 29: a reference to Shannon’s attitude to fame

Keywords for this question: Shannon’s attitude, fame,  

The answer lies in paragraph B where we find this line in the middle, “While at Bell Laboratories, Shannon developed information theory, but shunned the resulting acclaim.”

Here, shunned means turned away from. It means Shannon developed information theory but he avoided the fame he got from his invention. He disliked it.

So, the answer is: B

Question 30: details of a machine capable of interpreting incomplete information

Keywords for this question: machine, capable, interpreting, incomplete information,

Take a close look at paragraph E. Here, the writer says in lines 5-7, “Other codes have become part of everyday life – such as the Universal Product Code, or bar code, which uses a simple error-detecting system that ensures supermarket check-out lasers can read the price even on, say, a crumpled bag of crisps.”

Here, machine indicates to check-out lasers that can interpret (read) incomplete information (crumpled bag of crisps).

So, the answer is: E

Question 31: a detailed account of an incident involving information theory

Keywords for this question: detailed account, incident, information theory,     

The answer can be found in paragraph A where we come to know about the problem faced by Voyager I which received instructions through a radio signal from the earth to use its spare parts to operate correctly. The whole paragraph is a detailed description of how NASA was able to send radio signals light years away to the Voyager I prove.

So, the answer is: A

Question 32: a reference to what Shannon initially intended to achieve in his research

Keywords for this question: Shannon, initially, intended to achieve, his research,

In paragraph C, the writer indicates, “He (Shannon) set out with an apparently simple aim: to pin down the precise meaning of the concept of ‘information’.”

Here, set out with an apparently simple aim = initially intended to achieve

So, the answer is: C

Questions 33-37: (Note completion)

Title of the note: The Voyager I Space Probe

Question 33-34: The probe transmitted pictures of both 33. _________ and _________, then left the 34. _________.

Keywords for this question: transmitted pictures, both, left,    

As the word before question 33 is ‘both’, we can understand that the answers for question no. 33 will be same kind of things. If we look closely at paragraph A, we can find the description of Voyager I Space Probe’s mention. In lines 2-4, the writer says, “The space probe, Voyager I, launched in 1977, had sent back spectacular images of Jupiter and Saturn and then soared out of the Solar System on a one-way mission to the stars.”

Here, sent back = transmitted, images = pictures, soared out = left,

So, the answers are:

33. Jupiter, Saturn
34. Solar System

Question 35: Scientists feared that both the ________ and ________ were about to stop working.

Keywords for this question: Scientists, feared, both, about to stop working,    

In paragraph A take a look at lines 5-7, “Sensors and circuits were on the brink of failing and NASA experts realised that they had to do something or lose contact with their probe forever.”

Here, on the brink of failing = about to stop working,

So, the answers are: sensors, circuits,

Special Note: remember, you cannot write sensors and circuits as your answers. It is because the word ‘and’ is already present in the question. In the IELTS listening and Reading Test, it is PROHIBITED to write any word/words which is/are already written in the question.

Question 36: The only hope was to tell the probe to replace them with __________ -but distance made communication with the probe difficult.

Keywords for this question: only hope, replace, distance, made communication, probe, difficult,    

In paragraph A the writer talks about the solution of Voyager I problem. In lines 7-8 the author writes, “The solution was to get a message to Voyager I to instruct it to use spares to change the failing parts.”

Here, solution = the only hope, change = replace,

So, the answer is: spares

Question 37: A ________ was used to transmit the message at the speed of light.

Keywords for this question: transmit, message, speed of light

Take a look at the end of paragraph A. Here, the author says in lines 9-12, “By means of a radio dish belonging to NASA’s Deep Space Network, the message was sent out into the depths of space. Even traveling at the speed of light, it took over 11 hours to reach its target, far beyond the speed of Pluto.”

Here, the message was sent out = transmit the message,

So, a radio dish was used to send out message to Voyager I.

So, the answer is: radio dish   

Questions 38-40: (TRUE, FALSE, NOT GIVEN)

In this type of question, candidates are asked to find out whether:

The statement in the question agrees with the information in the passage – TRUE
The statement in the question contradicts  the information in the passage – FALSE

If there is no information on this – NOT GIVEN

[For this type of question, you can divide each statement into three independent pieces and make your way through with the answer.]

Question 38: The concept of describing something as true or false was the starting point for Shannon in his attempt to send messages over distance.

Keywords for this question: describing, starting point, true or false, the starting point, Shannon,

In paragraph C, the writer states in lines 3-6, “He set out with an apparently simple aim: to pin down the precise meaning of the concept of ‘information’. The most basic form of information, Shannon argued, is whether something is true or false – which can be captured in the binary unit, or ‘bit’, of the form 1 or 0.”

Here, set out = the starting point,

The lines clearly agree with the statement.

So, the answer is: TRUE

Question 39: The amount of information that can be sent in a given time period is determined with reference to the signal strength and noise level.

Keywords for this question: the amount of information, sent, the signal strength and noise level,      

The answer is in paragraph D as Shannon showed that the rate told us how much information passed in a given period of time. “Shannon showed that noise sets a limit on the rate at which information can pass along communication channels while remaining error-free. This rate depends on the relative strengths of the signal and noise traveling down the communication channel, on its capacity (its ‘bandwidth’).”

So, the answer is: TRUE

Question 40: Products have now been developed which can convey more information than Shannon had anticipated as possible.

Keywords for this question: convey more information, Shannon anticipated

Take a close look at the end of paragraph E, the writer says, “As recently as 1993, engineers made a major breakthrough by discovering so-called turbo codes – which come very close to Shannon’s ultimate limit for the maximum rate that data can be transmitted reliably, and now play a key role in the mobile videophone revolution.”

This means the products of the present time came close to what Shannon had anticipated, but could not convey more information. They could not exceed Shannon’s expectations.

So, the answer is: FALSE

 Click here for solutions to Cambridge 9 Test 3 Reading passage 1

 Click here for solutions to Cambridge 9 Test 3 Reading passage 2