How to Tackle Must Be True or Inference Critical Reasoning questions

It is one of the most common question categories in the GMAT Exam after the Weaken, Strengthen, and Assumption questions.

Structure of the question stem

The question stem usually will not contain a conclusion and you have to draw one (infer) from the information given in the question stem. So your question stem will contain just 2-3 factual statements NOT arguments.

The information given in the question stem will be true and valid unlike that in the assumption, weaken, and strengthen question stems, where the stem has an inherent weakness that needs to be mitigated (in case of strengthen questions) or further increased (in case of weaken questions)

The information in the question stem IS true irrespective of the ‘real-world’ scenario. For example if the question stem were to state that 'The Earth revolves around the moon' then we need to assume that it is the truth. We cannot bring in our real-world or outside knowledge,which is contradictory to the information provided in the question stem.

Many a times the question stem will contain numbers, percentages, and statistics and ask you to draw an inference based on the quantitative data. 

Words used in the question statement

The question stem will typically use some variation of the words:- 

Draw the conclusion

Infer

Most properly drawn

Best supported by

Must be true

POE:Process Of Elimination

An inference could be a logical deduction from a single statement or from a combination from two or more factual statements from the question stem.One should always keep in mind that the information in the options should always (not sometimes ) hold true with respect to the contents of the question stem.Always work from wrong to right eliminating the options that can be true or are sometimes true but NOT always true.

Common Traps

The inference drawn should always be valid .The most common trap on this type is something that could be true and might evenlikely to be true but does not necessarily have to be absolutely true.Inference questions can sometimes include the words ‘strongly supported by ‘ which also show up in Strengthen questions. If the question contains this language, check to see whether it refers to the answers as conclusions or inferences “ if so, this is an Inference question, not a Strengthen question. Strengthen questions will contain a conclusion in the argument, not in the answer choices.

Difference between Inference /Must be true and Other question types

While the test takers can easily get caught up by the use of familiar looking words in the question statements, one has to read closely and look for the exact information being sought to deduce the question type.

Difference between Inference (must be true) and Assumption questionsInference can be easily and directly deduced from the statements of the question stem while assumption will contain NEW information and can never be directly deduced from the question stem.

Difference between Inference (must be true) and Strengthen questions While Strengthen questions contains questions stems with inherent weakness or gaps in logic that need to be filled by the correct answer option,containing new information. Inference questions can be directly deduced from the question passage with the use of NO outside information.

Difference between Inference (must be true) and Conclusion (main point) questionsThe use of expressions such as ‘Draw a Conclusion’ or ‘Which of the following conclusions is best supported by' make it difficult for the test-takers to pick the correct question category, but in Conclusion

or Main point questions you will either be provided with a conclusion in the question stem or be asked to state the main point of the argument and wouldnot be asked to provide an inference as in the case of Must be true questions, which typically don't contain the conclusion of the argument in the question stem itself

Efficiently tackle Inference questions in CR and RC

Approach to RC Inference Type questions (may not apply in CR inferences):

•Inference answers are not readily identifiable. So ELIMINATION by “Word Justification” and “TRANSLATION” is the most critical skill. Do not select a half true answer in any case. Any statement that is inconsistent with the passage is always wrong.

•Inference questions will typically read: “The passage suggests which of the following about “XYZ”?” OR “Which of the following can be inferred from the passage about XYZ”? OR “Information in the passage implies which of the following about “XYZ”?

•Usually, do not select an answer that repeats VERBATIM information for inference questions.CONCEPT OF COMPLEMENT INFORMATION: 

If the question requires that we make an inference about COLD-BLOODED animals, it is most likely done on the basis of interpreting information in the passage about the COMPLEMENTARY group of WARM-BLOODED animals.

If the question requires us to infer the type of jazz music played BEFORE 1945, we will be required to interpret information about the type of jazz music played AFTER 1945.

If the passage mentions ‘married people’, the question may be about ‘unmarried people’.Let us say the passage is about a ‘recent theory about gold deposits’ then the question might be about an ‘earlier theory about gold deposits’.

If the passage says: “the customers were not leaving at an unacceptable rate for whatever reason”.We may infer that “company was able to retain customers at an acceptable rate.”

If the passage states that ‘Miles Davis and his group that assembled in a Harlem apartment in 1945 SLOWED DOWN the tempo of jazz music and STARTED featuring ensemble playing’. Our inference about the type of jazz music played BEFORE 1945 is that … the tempo was more rapid and SOLO playing (the complement of ensemble playing) was the norm.

•If the passage states that “Economists believe that further interest rate cuts will provide the needed acceleration to the sluggish economy.” Our inference on the basis of this statement will be that … the

‘economic progress is not dynamic and ‘needs’ to be speeded up.

•If the passage states that “Graduate School admission procedures since 1990 have always included Standardized test scores as a critical factor in the evaluation process.”Our inference about the ‘admission procedures’ prior to 1990 on the basis of this statement will be that … ‘prior to 1990’, Standardized test scores were not a critical factor in the evaluation process for admission to Graduate Schools.

•If the passage states that “Cold blooded animals were chosen for tests on the effects of temperatures on invading organisms because the temperatures of cold blooded animals can be easily controlled in a laboratory setting”. Our inference about the ‘warm blooded animals’ on the basis of this statement will be that … the ‘temperatures of warm blooded animals could not be easily controlled in a laboratory setting”.

•If the passage states that “Earth will receive a meteor shower during its yearly travel through the Geminid meteor stream”. Our inference will be that: the earth travels through the Geminid meteor stream ‘once a year’.

•If the passage states that “Unconditional guarantees deceptively suggest that the results can be guaranteed’. Our inference will be that: “Results” cannot be guaranteed.

•If the passage states that “The textile mill-owners chose women for jobs that required detailed attention and repetitive actions because they thought that women were more patient with such jobs”. Our inference will be: “Men were not patient with jobs requiring detailed attention and repetitive actions.”

•If the passage states that “Some economists believe that all companies should give away free shares to their employees in order to provide the needed acceleration of the privatization process.” Our inference will be: “According to some economists, the privatization process is proceeding slowly and needs to be speeded up.”

•If the statement reads, ‘the colonists suspected that the Massachusetts governor was involved in a CONSPIRACY to deprive them of their civil liberties’. Our inference will be that: the colonists believed that more than one person was involved in the scheme to deprive them of their civil rights.

•If the statement in the passage reads, ‘the administration’s tax cut proposals will provide the NEEDED stimulus to the American economy’, our inference will be: we would infer the adjective ‘needed’ to mean that the ‘American economy requires some incentive in the form of tax breaks to tax payers’.

•If the statement in the passage reads, “The Morrill Act of 1862 SUCCESSFULLY created land-grant institutions in the mid-western United States”. Our inference will be: ‘the Morrill Act of 1862 had the goal of creating land-grant institutions’. (‘Success’ implies achievement of a favorable or desired goal or outcome, and the use of the WORD ‘successfully’ suggests that the goal of the Act was to create the land- grant institutions).

•If the context-specific statement in the passage reads, “The earth association claims that, through its mailers to 2000 individuals, it CONVERTED 2000 individuals to its cause” Our inference will be that:

the ‘earth association makes an unverified statement that none of the 2000 individuals who received its mailers already believed in the cause that the association represents’.

•If the context-specific statement in the passage reads, “as a result of the breeding practices that led to increased productivity, the overall genetic variability of cultivated wheat has drastically declined in the last two centuries” Our inference will be: the “overall genetic variability of cultivated wheat was far greater 200 years ago”.

•If the context-specific statement in the passage reads, “the work of Miles Davis and his group that assembled in a New York city apartment in 1945 slowed down the tempo of Jazz music and featured ensemble playing as much as or even more than solo playing”. Our inference will be: ‘tempo of Jazz music was more rapid prior to 1945 and that Jazz music did not feature ‘ensemble playing’ before 1945 to the same extent as it did after 1945’.

•If the statement reads, “law-makers argue that if telecommunication equipment were allowed to be exported to Cuba, repression by Castro regime cannot indefinitely continue” Can we logically interpret that telecommunication equipment is the best way to prevent the struggle for freedom?oNO: do not creatively interpret ‘repression’ to mean ‘a struggle for freedom’ or the idea of‘exporting telecommunication equipment to Cuba’ to mean that ‘telecommunication equipment is the best way to prevent repression’.

•If the context-specific statement reads, “Watteau’s admirers BELIEVED that the images were genuine” Can we logically interpret that “Watteau’s admirers were UNWILLING to consider the possibility that the images were not genuine”?oNO: The fact that some BELIEVED something to be true does not necessarily mean that theywere ‘unwilling’ to accept other explanations.