UPSC Prelims CSAT Solved Papers

Directions: Read the following passage and answer the items that follow. Your answers should be based solely on the passage.

When SARS-CoV-2 was first detected in 2019, it was a truly novel virus for the world. At that time, no one in the world had been exposed to SARS-CoV-2 or had specific immunity against it. In contrast, people across the world have been exposed to HMPV for decades and the virus is well-studied. HMPV and SARS-CoV-2 belong to two very different virus families with fundamentally different characteristics and epidemiology, with strong seasonality seen in HMPV, unlike SARS-CoV-2. Both viruses cause different severity of symptoms, particularly over the long term, and the affected population segments do not fully overlap. In general, HMPV causes milder illness with deaths being very rare and with no long-term post-viral symptoms.

Which of the following conclusions is/are valid?

1. Though SARS-CoV-2 and HMPV are similar viruses with somewhat different epidemiology, the former became a pandemic because it was novel and people had not been exposed to it in the past.
2. The two viruses have fundamentally different impacts on human populations and should not therefore be dealt with in a similar manner.

Which of the following reflect the intent of the writer in the above passage?

1. To evolve methodologies for objective analysis of the two viruses
2. To establish the epidemiological similarities and differences between the two viruses
3. To offer a better understanding of the remedies of HMPV when analysed in conjunction with SARS-CoV-2

Which of the following statements reflect the logical and rational inferences that can be drawn from the passage?

1. HMPV has, historically, had longer documentation of studies when compared with SARS-CoV-2.
2. The two viruses are different from each other and this results in markedly different outcomes amongst those affected.
3. Long-term impacts of the two viruses are dissimilar and this is an important differentiator between them.
4. One of the common factors between the two viruses is seasonal specificity.

Three variables x, y and z take values 2, 3, 4 or 5 such that their values are always distinct. If M and N denote the largest possible value and the smallest possible value, respectively, for the expression {(x × y) + z}, then M − N is

Suppose x, y and z are variables taking positive real numbers as their possible values. It is given that y is directly proportional to x² and x is inversely proportional to z. For z = 7/25, the values of x and y are 5 and 50, respectively. If y = 98, what is z equal to?

Directions: Read the following passage and answer the items that follow. Your answers should be based solely on the passage.

India is starting to deploy AI for critical use cases such as weather forecasting, pest detection and control, and crop yield optimisation. However, penetration is limited to a small subset of tech-savvy farmers. In the US and in Europe, generative AI tools have started offering precision farming at scale, integrating large datasets to provide real-time agronomic insights. For at-scale integration and accessibility of AI tools in India, it would be helpful to develop Indian languages-based AI tools for smallholder farmers, partner with AgTechs to create affordable AI solutions, and disseminate AI-based advisory services through government programmes.

Which of the following assumptions is/are valid?

1. Agricultural productivity has marched ahead in the West because of the economies of scale facilitated by the adoption of AI tools.
2. Affordable AI tools rendered available in local languages can help AI-based solutions reach more and more small farmers.
3. Though penetration is as yet low, critical application areas deploying AI tools are already in use in India.

Which of the following statements is/are not correct?

1. Tech-savvy farmers will drive the AgTech companies of the future.
2. The development of advisory services by the government programmes for the use of AI tools in agriculture would be helpful.
3. In the US and Europe, AI tools have replaced traditional agricultural practices.
4. The integration of large datasets for use in real-time agronomic analysis is already a reality.

P, Q, R, S and T are ranked 1 to 5 (not necessarily in that order). The rank of P is 4, the rank of Q is not 5, the rank of R is 1, the rank of S is not 2, the rank of T is not 3. Then which of the following is/are correct?

I. If the rank of S is 3, then that of T is 2.
II. If the rank of Q is 3, then that of T is 5.

Two identical straight rods are painted in five distinct colours so that each of them gets divided into five equal parts along the length. In one of them, the portions are marked P1, P2, P3, P4 and P5 (not necessarily in that order) whereas in the other, they are marked Q1, Q2, Q3, Q4 and Q5 (not necessarily in that order). When the rods are kept parallel to each other side by side, P1 and Q3 match, P4 matches Q1 or Q2, and Q4 matches P3 or P5. If Q3 and Q5 are adjacent, which of the following is/are possible?

I. Q3 is marked at the middle portion of the straight rod.
II. P2 is marked at one of the extreme portions of the straight rod.

Seven persons A, B, C, D, E, F and G travel by three cars X, Y, Z. A and another two of them travel by X. Only E travels with G. C travels by Z, but B does not travel by Y. Besides, A and B do not travel by the same car. Then which of the following are correct?

I. No one travels alone.
II. Only D travels with F.
III. Only C travels with B.

There are four statements X, Y, Z and W. Their relations are as follows:
If X is incorrect, then so is Z; if Y is incorrect, then W is correct; if W is correct, then X is incorrect.

Which of the following is/are correct?

I. If X is correct, then so is Y.
II. If Z is correct, then it is not necessary that Y is correct.

X and Y are two runners who run for the same duration of time on the same circular track. They started running at the same time in the same direction with uniform speeds. When X completed 7 rounds, Y did exactly 5. After completing 5 rounds, Y changed his direction and started running in the opposite direction with speed which is double of his earlier speed. On the other hand, X continued to run with the same speed. They stopped running when X completed exactly 21 rounds. How many times did X and Y meet after they had started and before they finally stopped?

In an objective type question paper, 5 marks are awarded for a correct answer and 2 marks are deducted for a wrong answer. A student attempted all the questions and got a score of 69. Had he been awarded 4 marks for a correct answer and 1 mark deducted for a wrong answer, he would have scored 84. How many questions were there in the question paper?

Directions: Read the following passage and answer the items that follow. Your answers should be based solely on the passage.

The Juvenile Justice (Care and Protection of Children) Act, or the JJ Act, 2015 allows for the possibility for trying adolescents above 16 as adults if they are accused of committing a heinous offence. A heinous offence is one with a minimum punishment of seven years. Offences such as culpable homicide and causing death by negligence, which are common in drunken driving cases, are not heinous offences because they do not have a prescribed minimum punishment. The JJ Act, amended in 2021, now categorises an offence that has no minimum sentence, but has a maximum sentence of seven years or more as a serious offence which nonetheless, in the opinion of activists, does not merit the transfer of a case to the adult criminal justice system.

Which of the following conclusions is/are valid?

1. Only a serious offence as categorised by the revised JJ Act, justifies the transfer of a case to the adult judicial system.
2. The JJ Act, 2021, categorises an offence as a serious offence based on the maximum sentence it carries, rather than on the minimum sentence.

Which of the following statements is/are correct?

1. If an offence has no minimum prescribed punishment, it cannot be considered heinous as per the JJ Act, 2015.
2. As per the JJ Act, 2021, an offence for which there is a provision for a maximum sentence of seven years or more, but no minimum sentence, is to be considered a serious offence.

An explosion takes place at a certain distance from an army camp. As soon as the sensor in the camp receives the sound of the explosion, a drone starts flying towards the spot of explosion. The drone clicks a picture from the spot and the camp receives it at the same time. Immediately another drone starts flying to the spot and it also sends a picture as soon as it reaches the spot. The two pictures were received at 5:02 PM and 5:05 PM, respectively. If the speed of the drones is 30 m/s, at what time did the explosion take place? Assume that the speed of sound is 300 m/s.

The digit in the unit place of the number 6¹²⁹ × 7³⁰⁷ is

A person saves 10% of his salary every month. If his salary increases by 12% and the expenditure increases by 10%, then what will be the change in his saving per month?

P has a son and a daughter. S is the mother of T. S is R's spouse. Q and R are children of P. Then how is Q related to S?

How many three-digit numbers can be expressed as an integral power of 2?

Directions: Read the following passage and answer the items that follow. Your answers should be based solely on the passage.

The key source of the battle for clean skies and clear lungs is the fuel we burn—from household Chulhas to the thermal power plants. In most cases, it is biomass or coal. The Supreme Court banned the use of pet coke—the dirtiest of such fuels. The Delhi Government banned the use of coal, which was later extended to the entire National Capital Region. It was also agreed that the thermal power plants would clean up or shut down. Action on this has been patchy to say the least. The lesson from the transition to CNG is that people need alternatives for a ban to be effective. When diesel buses were stopped, CNG supply had to be assured. It also had to be feasible in terms of cost. The Supreme Court agreed that fiscal measures were needed to keep clean fuel cheaper than dirty fuel. Now even as coal is banned, the price of natural gas makes industry uncompetitive.

Which of the following inferences is/are correct?

1. The source of the energy we consume is the key to the battle for cleaner air.
2. Bans are effective where the will is strong and the people are convinced that such bans are for the greater good of society.
3. There is judicial approval for a policy that intervenes fiscally to facilitate benevolent pricing for cleaner fuel.

Which of the following statements is/are correct?

1. Thermal power stations in Delhi were required to summarily shut down.
2. CNG supplies had to be assured once diesel vehicles were prohibited from plying.
3. The Supreme Court banned the use of coal across the National Capital Region.

Consider the following statements:
Every red is blue. Every blue is green. Every green is yellow.

Which of the following statements denoted by P, Q and R are correct?
P. Every blue is yellow.
Q. Every red is green.
R. Every red is yellow.

How many times does 5 appear in all two-digit positive integers?

X travels 6 km on a bicycle with average speeds of 5 km per hour, 10 km per hour and 4 km per hour during the first 1 km, the next 2 km and the remaining 3 km, respectively. Y travels the same distances with average speeds of 4 km per hour, 10 km per hour and 5 km per hour, respectively. How many minutes early will Y complete the journey if both X and Y start at the same time?