UPSC CSAT Simplified: Expert tips to solve Logical Reasoning and Analytical Ability questions (PART 3)

About our expert: For UPSC aspirants grappling with the challenges of CSAT, Dr. Mansoor Agha Siddiqui brings decades of experience to the conversation. With over three decades of guiding students through aptitude and assessment tests such as GMAT, IIM-CAT, GRE, SAT, LSAT, CUET and others, he has worked extensively with the design and demands of aptitude-based examinations. His expertise also includes mentoring UPSC aspirants across multiple areas, including CSAT, making his insights particularly relevant for candidates preparing for this crucial paper.

CSAT SIMPLIFIED: Click for Part 1 | Click for Part 2 | Click for Part 3 | Click for Part 4 

Part 3: Logical Reasoning and Analytical Ability

Logic is the study of methods and principles used to distinguish between correct and incorrect reasoning. We all use reasoning to wade through our real world. Although we may not know how to reason in the technically correct manner that fetches marks in an Aptitude or Intelligence Test. 

Reasoning is a major component of every aptitude test, though the exact type of questions depends on the purpose of the aptitude test. A Civil Servant will need to be objective and not get swayed by assumptions, fallacies, extrapolations and prejudices. 

In Logical Reasoning, questions can be based on a short passage, graphical or tabulated information or a cluster of conditions. 

On the other hand, Analytical Ability questions measure a candidate’s ability to analyse a given structure of arbitrary relationships and deduce the missing information from that structure. Analytical Ability becomes even more important, later, as it would help you as a true-blue IAS officer in maintaining protocols of organizing events and meetings. 

The Analytical Ability questions simulate the kinds of detailed analyses of relationships that an IAS officer must be adept at handling. For example, a passage might describe eight diplomats sitting around a table, following certain rules of protocol as to who can sit where. You must answer questions about the implications of the given information, for example, who is sitting between diplomats X and Y.

The next set of 5 questions test Analytical Ability skills

Read the following passage and answer the 5 (five) items that follow:

The letters A, B, C, D, E, F and G, not necessarily in that order, stand for seven consecutive integers. The maximum value of any of these integers is 10.

(i)       D is 3 less than A.

(ii)      B is the middle term.

(iii)     F is as much less than B as C is greater than D.

(iv)     G is greater than F.

1.  The fifth integer is:

(a) A             (b) B

(c) C             (d) D

 2. A is as much greater than F as which integer is less than G ?

(a) A             (b) B

(c) C             (d) D

 3. If A = 7, the sum of E & G is

(a) 5             (b) 10

(c) 12           (d) 14

 4. A – F = ?

(a) 1             (b) 2

(c) 3             (d) 4

 5.  The third integer is:

(a) B            (b) D

(c) E            (d) F

Explanation: The given information can be tabulated and the missing information can be figured out as follows:

So, correct answers for questions 1-5 are

1     (c)     C

2     (d)     D

3     (b)     2 + 8 =10

4     (d)     7 – 3 = 4

5     (b)     D

The next set of 3 questions test Logical Reasoning skills

Directions for the following 3 (three) items:  Read the following three passages and answer the items that follow. Your answers to these items should be based on the passages only.

Passage — 1

Albinism is a rare genetic condition that inhibits the production of melanin, or pigmentation, in the skin and hair. People born with albinism are unusually susceptible to sunburn, melanoma, and a range of other health issues that are generally connected to excessive exposure to the sun.

6. The statements above, if true, provide the most support for which of the following conclusions?

(A) People born with albinism develop other biological protections against melanoma and other sun-related health issues.

(B) Humans with a high production of melanin can easily ignore health issues related to exposure to the sun.

(C) When a non-albino person gets sunburn, the amount of melanin produced by that person decreases.

(D) In humans, melanin plays a role in protecting the skin from developing sunburn and other sun-related ailments.

Passage — 2

Celiac disease results from an inability of the digestive tract, specifically the small intestine, to absorb gluten, a protein found in wheat, barley, and certain other grains. The body’s immune system attacks the gluten as if the protein were a harmful pathogen, often resulting in serious damage to the intestinal lining. People who suffer from celiac disease must eliminate gluten from their diets. Symptoms of the disease include abdominal cramps, bloating, and anaemia.

7. If the statements above are true, which of the following assertions can be made on the basis of them?

(A) Anyone who suffers from celiac disease will experience anaemia.

(B) Eliminating gluten from one’s diet will cure celiac disease.

(C) People experiencing abdominal cramps, bloating, and anaemia have celiac disease.

(D) The human body cannot always recognize harmless substances.

Passage — 3

According to a recent magazine article, of those office employees who typically work 8 hours at the office each day but sometimes say that they will work at home on a particular day, 25 percent actually work less than one hour. At the same time, over 90 percent of those same office employees believe they are more productive working at home than working in their office.

8. The statements above, if true, best support which of the following conclusions about the office employees discussed in the article?

(A) On average, the office employees working at home for a day work fewer hours than office employees working at the office.

(B) 10 percent of the office employees are less productive working from home than working in their office.

(C) At least 15 percent of the office employees do not define productivity exclusively in terms of the number of hours worked.

(D) At least 25 percent of the office employees can complete the same amount of work in one hour at home as in 8 hours at the office.

So, correct answers for questions 1-5 are:

Solution 6

This argument provides that albinos, or people whose bodies do not produce melanin, are unusually susceptible to solar exposure. This suggests a connection between the production of melanin in humans and protection from sunburn and other sun-related ailments; we should look for a conclusion that draws this connection.

(A)     INCORRECT – The argument does not indicate that people born with albinism somehow develop other natural defenses against sun-related health issues.

(B)     INCORRECT – This conclusion is too extreme to be supported by the argument; nothing in the argument suggests that humans whose bodies produce high levels of melanin can “easily ignore” sunburn or other sun-related health issues.

(C)     INCORRECT – There is no indication in the argument that sunburn reduces melanin production.

(D)     CORRECT. The argument does strongly suggest that melanin plays some role in protecting the skin from developing sunburn and other sun-related ailments, since albinos do not produce melanin and are unusually susceptible to sun-related ailments.

Solution 7

The text tells us that celiac disease results when the body mistakes gluten for a harmful pathogen, causing damage to the intestine. We are also told that gluten is a protein found in certain grains, and that people suffering from celiac disease must eliminate it from their diets. Finally, we are told that symptoms of the disease include cramps, bloating, and anemia. We need to find an answer choice that is inferable from these facts alone.

(A)     INCORRECT – Anemia is just one of several symptoms of the disease. We do not know whether everyone who has the disease will also develop anemia.

(B)     INCORRECT – We do not know whether eliminating gluten will cure the disease, only that people with the disease must not eat gluten. Perhaps the disease will exist anyway in a latent form.

(C)     INCORRECT – We do not know whether the symptoms mentioned are also symptoms of other conditions.

(D)     CORRECT. If the body mistakes gluten for a harmful pathogen, then it must be true that the body cannot always recognize harmless substances.

Solution 8

The passage presents information about what office employees who work 8-hour days and who have worked at home told a certain magazine. The first piece of information is about what some of those office employees actually do: 25 percent of office employees actually work less than an hour on days that they work at home. The second piece of information is about what some of those office employees believe: 90 percent believe that they are more productive working at home than at the office. A proper CSAT conclusion must be provable by those two pieces of information.

(A)     INCORRECT – The passage only provides information about the working hours of 25 percent of the office employees. The passage does not provide any information regarding the working hours of the other 75 percent; hence, it is not possible to conclude anything about the office employees on average. For example, it is possible that the other 75 percent of the office employees work 14-hour days when working from home. It is also possible that they work 6-hour days when working from home.

(B)     INCORRECT – The passage provides no information about the actual productivity of any of the office employees. It only provides information about what the office employees believe about their productivity.

(C)     CORRECT. 90 percent of the office employees believe that they are more productive at home than at work. At the same time, 25 percent of the office employees actually work fewer hours when they work at home than when they work at the office. The overlap between these two groups is at least 15 percent of all of the office employees. This group of employees believes that they are more productive at home than at work and yet this group actually works fewer hours at home than at work. Thus, these employees must not define productivity exclusively in terms of the number of hours worked.

(D)     INCORRECT – The passage discusses the actual work hours of 25 percent of the office employees. Then it describes the beliefs of 90 percent of office employees regarding their productivity. First, there is no necessary link between an individual’s beliefs about his or her productivity and that individual’s actual productivity; hence, no conclusion can be made regarding actual productivity from the information about beliefs. Second, the number of hours worked alone is not an indication of productivity; it is possible, for example, that an employee who works 1 hour is more productive in terms of work done per hour than when he works 8 hours and yet that employee might still accomplish more total work when working 8 hours. Therefore, it is not possible to conclude anything regarding productivity for any of the office employees.

Next Article in CSAT Simplified: How to solve General Mental Ability questions

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