UPSC CSE Prelims Paper 2 (CSAT) Mock Test - 3 Free Online Test 2026

Let the original sum of money be P, and the rate of interest per annum be R%
After 2 years, the amount becomes 2.25 times the original sum.
So, the amount after 2 years is 2.25P.
The formula for compound interest:
Amount = Principal × (1 + Rate/100)^Time
So, 2.25P = P x (1 + R/100)²
or 2.25 = (1 + R/100)²
or √2.25 = 1 + R/100
or √2.25 - 1 = R/100
or 1.5 - 1 = R/100
or 0.5 = R/100 or R = 50
Therefore, the rate of interest is 50%.
Hence, option (d) is the correct answer.

• Inference 1 is incorrect. The line “Though certified organic crop producers earn higher revenue, they incur higher production expenses as well”, shows that the production cost of organic farming is high. However, nowhere has it been mentioned in the passage that research on farm level data will help in reducing the cost of organic farming. Therefore, this inference is not correct.
• Inference 2 is incorrect. Refer to the line: ―Though certified organic crop producers earn higher revenue, they incur higher production expenses as well” and “Contrary to expectations, certified organic farmers do not earn significantly higher household income than conventional farmers.” The revenue might be high in organic farming sector, but the input cost is also high. So, the net profit (revenue – input cost) might not be significantly higher in organic farming.  Therefore, this inference is not correct.

• Option (a) is incorrect. As per the passage “Contrary to expectations, certified organic farmers do not earn significantly higher household income than conventional farmers.” Conventional farming is not more profitable than organic farming but is mildly less profitable. So, to say that conventional farming is highly profitable is not correct.
• Option (b) is incorrect. Refer to the lines “There is growing evidence that organic farming is a rapidly expanding economic sector in the U.S.” Clearly, organic farming is expanding rapidly in the U.S. It is incorrect to say that organic farming is witnessing reduced growth in the U.S.
• Option (c) is correct. The lines “Though certified organic crop producers earn higher revenue; they incur higher production expenses as well. In particular, certified organic producers spend significantly more on labour, insurance, and marketing charges than conventional farmers”, reflect that organic farming involves higher input costs which reduces the net profits. Therefore, as per the passage, it would be correct to say that rationalising these expenses will help in making organic farming more profitable.
• Option (d) is incorrect. The passage deals mostly with the economic aspects of organic farming vis-à-vis conventional farming. The environmental aspects are not touched upon in the passage. Therefore, this answer option is incorrect.

Profit = 25%
Selling price = ₹ 3920
∴ Cost price = ₹ {(3920/125) × 100} = ₹ 3136
Profit = Selling price – Cost price = 3920 - 3136 = ₹ 784
Hence, option (c) is the correct answer.

Let cost price of mangoes be ₹ x
Ramesh’s profit is 20%.
∴ Selling price = 120% of x = 6x/5
Suresh sells the mangoes at double the price.
So, selling price of Suresh = 12x/5
Profit = SP – CP = (12x/5) – x = ₹ 7x/5
∴ Profit percent = (Profit / CP) × 100 = (7x/5) × (1/x) × 100 = 140%
Hence, option (c) is the correct answer.

Let the initial amount invested be A.
Return on investment for the first year is 10% and for subsequent years is 20%.
Amount after 1 year = (110/100) × A = 1.1A
Amount after second year = (120/100) × 1.1A = 1.1A × 1.2
Similarly, amount after six years = 1.1 × (1.2)⁵ A
Hence, option (d) is the correct answer.

Let the initial length and breadth of a rectangle be l and b respectively.
Initial area of rectangle = l × b = lb
New Length after it got increased by 20% = 120/100 × l = 1.2l
New Breadth after it got increased by 25%= 125/100 × b = 1.25b
New Area = 1.2l × 1.25 b = 1.5lb
Net change in area = New Area – Initial area = 1.5lb – lb = 0.5lb
Percentage increase in area = Net increase in area / original area × 100 = 0.5lb/lb × 100 = 50%
Hence, option (c) is the correct answer.

Let salary of C = ₹ 100
Salary of A = ₹ 130
Salary of B = ₹ 140
According to the question,
(130/140) × 100 = X
Or X = 650 / 7
Or X = 92 (6/7)
Hence, option (d) is the correct answer.

• Assumption 1 is incorrect. The passage talks about data protection in general, and the need to balance the benefits and the risks of personal data processing. There is no mention about whether or not India has a robust data processing framework. Therefore, this answer option is incorrect.
• Assumption 2 is correct. The given assumption is correct as it validates the line “A strong data protection framework provides certainty which may encourage investment, competition and innovation in the digital economy and uptake of digital government and private sector services.” Therefore, it is correct to say that data protection is important both for privacy concerns and economic growth of the country.

• Option (a) is incorrect. The given statement is not correct because the passage does not mention the context of “high incidences” of the misuse of personal data. The author only says that data processing frameworks should ensure that individuals have confidence that their data is collected and stored safely and used solely for legitimate purposes. Therefore, this answer option is incorrect.
• Option (b) is correct. Refer to the line: ―Governments, organisations, and individuals increasingly generate, collect and process personal data.” There are diverse stakeholders. Furthermore, data protection laws typically require personal data processing to be lawful, limited, transparent, accurate and secure. On top of it individuals’ need some control over how personal data about them is processed. All this makes the development of a strong data protection regime is a complex process. This answer option is correct.
• Option (c) is incorrect. As discussed above, framing a strong data protection regime is a complex task.
• Despite this complexity, the author is optimistic about the formulation of this regime. The author says that a strong data protection framework provides certainty which may encourage investment, competition and innovation. Had it been impossible to achieve, the author would not talk about the benefits of having a data protection regime. Therefore, it is incorrect to say that a strong data protection framework is impossible to achieve.
• Option (d) is incorrect. The author mentions that governments, organisations, and individuals increasingly generate, collect and process personal data. So, they are important stakeholders in data processing framework. The passage also mentions the concerns of individuals – privacy concerns, some control over how personal data about them is processed, etc. However, we cannot say that the concerns of the individuals should be ranked higher than that of governments and private sector.

Let principal be ₹ P.
Amount = ₹ 2P, Time = 12.5 = 25/2 years, Rate = R%
Simple interest = 2P – P = ₹P
Simple interest = (Principal × Rate × Time)/100
Or P = (P × R × 25)/(2 × 100) Or R = 8%
New Amount = ₹ 3P, Principal = ₹ P, R = 8%
Simple interest = 3P – P = ₹ 2P
So, Time = (Simple interest × 100)/(Principal × Rate) = (2P × 100)/(P × 8) = 25 years
Hence, option (b) is the right answer.

Let total cost price of lemons be ₹ 300.
Statement 1: According to statement 1, overall profit should be 25%.
∴ Total selling price = 300 + 300 × 25/100 = 300 +75 = ₹ 375
Now, C.P. of 1/3rd lemons, CP₁ = ₹100
and C.P. of 2/3rd lemons, CP₂ = ₹200
Selling price of 1/3rd lemons, SP₁ = 100 × 20/100 = ₹ 120
∴ Selling price of 2/3rd lemons,
SP₂ = Total selling price – Selling price of 1/3rd lemons = 375 – 120 = ₹255
So, Required percentage = {(255 – 200) / 200} × 100 % = 27.5%
So, statement 1 is right.
Statement 2: SP₂ = 255 and SP₁ = 120 So, SP₂ is more than double of SP₁.
So, statement 2 is not correct.
Hence, option (a) is the correct answer.

Increase in profit in scheme A in 2016 = 100 - 45 = 55
Increase in profit in scheme B in 2018 = 70 - 45 = 25
Required percent = (55 × 100)/25 = 55 × 4 = 220%
Hence, option (b) is the correct answer.

Let the selling price of 1 article = Rs. 1.
So the selling price of 16 articles = Rs. 16.
And loss = Rs. 4 So the cost price = 16 + 4 = Rs. 20.
Hence the percentage of loss = 4/20 × 100 = 20%
Hence, option (c) is the correct answer.

Satya buys a pair of slippers for ₹500 and sells them to Sachin at a profit of 20%.
∴ Cost price for Sachin = 120% of 500 = (500 x 120)/100 = ₹ 600
Sachin sells the slippers to Nitin at a profit of 10%.
Cost price for Nitin = 110% of 600 = (600 × 110)/100 = ₹ 660
Checking each statement.
Statement (i): Sachin paid ₹ 600, which is ₹ 100 more than what Satya paid.
Statement (ii): Nitin gave ₹ 660 to Sachin, not Satya.
Statement (iii): Sachin gave ₹600 to Satya
So, statements (i) and (iii) are correct.
Hence, option (b) is the correct answer.

Preserving earth’s cyclical processes by protecting terrestrial ecosystems and natural sinks is more equitable and cost-effective for addressing the climate crisis than current methods. This approach involves:

• Conserving natural sinks.
• Enhancing biodiversity protection.
• Restoring ecosystems.
• Involving indigenous people and local communities in agricultural practices.

Ultimately, the real issue is that human consumption has surpassed the planet's regenerative capacity, not merely the climate crisis itself.

(d) Straight from the passage but with different words. 

The number of red pens = 10  
The number of black pens = 10 + 3 = 13  
The number of blue = 10 - 5 = 5  
Total number pens in the box = 10 + 13 + 5 = 28  
Hence, 28 pens are there in the box.

Length of each piece = 31/4 = 13/4 m
Maximum pieces that can be cut = 30/(13/4) = 9
∴ Rod left = 30 - (13/4 )x 9 = (120 – 117)/4 = 3/4 m
∴ Required fraction = 3/4/30 = 1/40 

First, find the largest row‐size that divides 30, 45, and 60.

• The common divisors of 30, 45, and 60 are 1, 3, 5, and 15.

• The greatest is 15.

So each row can have 15 plants (all of the same variety).

• Number of rose‐rows = 30 ÷ 15 = 2

• Number of hibiscus‐rows = 45 ÷ 15 = 3

• Number of jasmine‐rows = 60 ÷ 15 = 4

Total rows = 2 + 3 + 4 = 9.

Hence, the minimum number of rows required is 9.

Solution:

1. Mark the three Sociology positions

   • Clue: “Second, fifth, and sixth books are Sociology.”

   • So:
     1 – – – – – – –
     2 → SOC
     3 – – – – – –
     4 – – – – – –
     5 → SOC
     6 → SOC
     7 – – – – – –
     8 – – – – – –

2. Place the two Governance books

   • Clue: “Two Sociology books are between two Governance books.”

   • The only adjacent SOC pair is at positions 5 and 6, so Governance must be at 4 and 7 (bracketing those two Sociologies).

   • Now:
     1 – – – – – –
     2 → SOC
     3 – – – – – –
     4 → GOV
     5 → SOC
     6 → SOC
     7 → GOV
     8 – – – – – –

3. Place the two Physical Geography books

   • Clue: “One Sociology book is between two Physical Geography books.”

   • Only the SOC at position 2 can lie between two as‐yet unassigned slots (positions 1 and 3).

   • So: 1 → PG, 2 → SOC, 3 → PG.

4. Place the single Economics book

   • Clue: “The book above Economics is a Governance book.”

   • GOVERNANCE slots are at 4 and 7.

   • If GOV at 4, ECO would go at 5—but 5 is already SOC, so that fails.

   • GOV at 7 means ECO must be at 8 (directly below 7), which is free.

5. Final arrangement (top → bottom, positions 1 to 8)
   1 → PG
   2 → SOC
   3 → PG
   4 → GOV
   5 → SOC
   6 → SOC
   7 → GOV
   8 → ECO

Answer: The last book from the top is the one on Economics.

Solution : 

1. From the earlier arrangement (top to bottom):
   1 → Physical Geography
   2 → Sociology
   3 → Physical Geography
   4 → Governance
   5 → Sociology
   6 → Sociology
   7 → Governance
   8 → Economics

2. The bottom four positions (5, 6, 7, 8) are:
   – 5 → Sociology
   – 6 → Sociology
   – 7 → Governance
   – 8 → Economics

3. Among the four subjects (Physical Geography, Governance, Sociology, Economics), Physical Geography does not appear in positions 5–8.

Answer: A Physical Geography book is not present within the bottom four rows.

Solution:

From the arrangement (top → bottom):

1 – Physical Geography
2 – Sociology
3 – Physical Geography
4 – Governance
5 – Sociology
6 – Sociology
7 – Governance
8 – Economics

• Odd positions (1, 3, 5, 7) hold: PG, PG, SOC, GOV

• Even positions (2, 4, 6, 8) hold: SOC, GOV, SOC, ECO

Sociology appears at odd (5) and even (2, 6).
Governance appears at odd (7) and even (4).

Answer: Sociology and Governance

Explanation of Relationship:

1. “My grandparents” are Prabhu’s grandparents.

2. “The only daughter of my grandparents” therefore refers to Prabhu’s mother (she is the sole female child born to those grandparents).

3. The girl in question is “the only daughter of [that only daughter of my grandparents],” meaning she is the only daughter of Prabhu’s mother.

4. Thus the girl is Prabhu’s mother’s daughter—i.e., Prabhu’s sister.

Answer Option C – Sister 

Solution:

1. List people, institutions, and known jobs

   • Persons: Ajay, Bala, Chandru, Dinesh, Ezhil, Farook, Guna

   • Institutions: L, M, N, P, Q, R, S

   • Jobs: Engineer, Accounts Officer, Doctor, Call Center Assistant, Teacher, Hotel Manager, Quality Inspector

2. Fill in the clues one by one

   • Chandru → Institution N; job is neither Quality Inspector nor Teacher.

   • Ezhil → Institution R; job = Doctor.

   • Ajay → job = Hotel Manager; institution ≠ L, Q.

   • “Accounts Officer works for M.”

   • “Call Center Assistant works for L.”

   • Farook → Institution Q.

   • Guna → Institution P; job = Quality Inspector.

   • Dinesh ≠ Accounts Officer.

3. Assign M (Accounts Officer)

   • If Bala were at M, she’d be Accounts Officer.

   • Dinesh cannot be Accounts Officer, so Dinesh ≠ M.

   • Ajay is Hotel Manager, so he can’t be Accounts Officer → Ajay ≠ M.

   • Therefore Bala must occupy M and hold Accounts Officer.

4. Assign L (Call Center Assistant)

   • The only unassigned candidate for L is Dinesh (everyone else has an institution or can’t be L).

   • So Dinesh → L, job = Call Center Assistant.

5. Place Ajay

   • Remaining institutions are S (since N, R, Q, P, M, L are taken).

   • Ajay cannot be L or Q, so Ajay → S, job = Hotel Manager.

6. Assign remaining jobs and institutions

   • Unfilled persons: Chandru (N), Farook (Q), Guna (P) is already filled, Ezhil (R) is done, Bala (M) is done, Dinesh (L) is done, Ajay (S) is done.

   • Available jobs now are Engineer and Teacher.

   • Chandru (N) cannot be Teacher (clue), so Chandru → N, job = Engineer.

   • That leaves Farook → Q, job = Teacher.

7. Verify all assignments

   • Ajay: S, Hotel Manager

   • Bala: M, Accounts Officer

   • Chandru: N, Engineer

   • Dinesh: L, Call Center Assistant

   • Ezhil: R, Doctor

   • Farook: Q, Teacher

   • Guna: P, Quality Inspector

All clues are satisfied.

Answer: Bala works as the Accounts Officer.

Dinesh works for Institution L.

1. Accounts Officer at M: Since “the Accounts Officer works for M,” whoever fills M must hold that post. Dinesh is explicitly ruled out as Accounts Officer, so Dinesh cannot be at M.

2. Call Center Assistant at L:

   • Clue: “The one who works for Institution L works as a Call Center Assistant.”

   • That means whichever friend ends up at L must be the Call Center Assistant.

3. Assigning Ajay and Others:

   • Ajay is Hotel Manager and cannot be at L or Q.

   • Farook is at Q.

   • Guna is at P (as Quality Inspector).

   • Ezhil is at R (as Doctor).

   • Bala, as Accounts Officer, must be at M.

   This leaves only Dinesh and Chandru to fill the remaining institutions L and N.

4. Chandru’s Role Rules Out L for Him:

   • Chandru works at N and is neither Quality Inspector nor Teacher.

   • Therefore, Chandru cannot occupy L (because L’s slot is the Call Center Assistant).

5. Conclusion for Dinesh:

   • Since Chandru must take N, the only open institution left for Dinesh is L.

   • At L, Dinesh automatically becomes the Call Center Assistant (per the clue).

Hence, Dinesh works for Institution L (as the Call Center Assistant).

Chandru’s profession is Engineer.

Brief Reasoning:

• We know Chandru is at institution N.

• The roles already assigned to other institutions are:

  • R → Doctor (Ezhil)

  • Q → Teacher (Farook)

  • P → Quality Inspector (Guna)

  • M → Accounts Officer (Bala)

  • L → Call Center Assistant (Dinesh)

  • S → Hotel Manager (Ajay)

• The only remaining profession for institution N is Engineer.
  Hence, Chandru works as an Engineer.

Farook works as a Teacher.

Brief Reasoning:

• Ezhil → Doctor at R

• Guna → Quality Inspector at P

• Bala → Accounts Officer at M

• Dinesh → Call Center Assistant at L

• Ajay → Hotel Manager at S

• Chandru → Engineer at N

The only institution left is Q, and the only remaining profession is Teacher. Since Farook works for Q, Farook must be the Teacher.

A correct combination is:

Guna – Quality Inspector – Institution P

(Other valid triples are:

• Ezhil – Doctor – R

• Bala – Accounts Officer – M

• Dinesh – Call Center Assistant – L

• Ajay – Hotel Manager – S

• Farook – Teacher – Q

• Chandru – Engineer – N )

General form : m₁ x d₁ = m₂ x d₂
Men complete work in 2 days whereas boys take 2 days more than men.
So 3 boys take 5 days to compete the same work. Convert all values in terms of men or boys
m₁ = 5m, d₁ = 2 :: m₂ = 3b, d₂ = 5
5m x 2 = 3b x 5
2m = 3b

Substitute m value in 10m + 3b = ?  

If 3 boys (m1) take 5 days (d1) to complete a work, then 18 boys (m2) takes how many days? (d2)