RRB NTPC Graduate Level (24th march 2026 Shift 2) — RRB NTPC 2025

• Key Fact: Acid rain is primarily caused by the emission of Sulphur dioxide ($SO_2$) and Nitrogen oxides ($NO_x$) into the atmosphere.

• Supporting Detail: These gases react with water, oxygen, and other chemicals in the atmosphere to form sulfuric acid and nitric acid, which then fall to the ground mixed with rain, snow, or fog.

• Why others wrong: Methane and Ozone are powerful greenhouse gases contributing to global warming but do not form acid rain. Ammonia is a basic (alkaline) gas, though it can react with acids in the air to form fine particulate matter.

• Exam Trick: Acid Rain = $SO_2$ (Sulphur dioxide) + $NO_x$ (Nitrogen oxides).

• Key Fact: C. Rajagopalachari (often called Rajaji) led the Salt Satyagraha in the Madras Presidency in April 1930, mirroring Gandhi's Dandi March.

• Supporting Detail: He organized a march from Trichinopoly (Tiruchirappalli) to Vedaranyam on the Tanjore coast to break the oppressive salt laws imposed by the British.

• Why others wrong: Sarojini Naidu famously led the non-violent protest at the Dharasana Salt Works in Gujarat. Sardar Patel was highly active in Gujarat (Bardoli). K. Kamaraj participated in the movement but was not the primary leader of the Vedaranyam march.

• Exam Trick: South India / Madras Salt March = Vedaranyam March = C. Rajagopalachari.

• Key Fact: The 89th Constitutional Amendment Act of 2003 established the National Commission for Scheduled Tribes (NCST) as a separate constitutional body.

• Supporting Detail: Prior to this amendment, there was a combined National Commission for SCs and STs (established by the 65th Amendment). The 89th Amendment bifurcated it by amending Article 338 and inserting a new Article 338A for the NCST.

• Why others wrong: The 102nd Amendment (2018) gave constitutional status to the National Commission for Backward Classes (NCBC) under Article 338B. The 97th Amendment deals with Co-operative Societies.

• Exam Trick: Article 338 = SC Commission. Article 338A = ST Commission (added by 89th CAA). Article 338B = OBC Commission (added by 102nd CAA).

• Given: Time taken for 2 pages = 40 minutes. Number of pages to be typed = 84.

• Basic Method (Solution):
Step 1: Calculate the time taken to type 1 page using the unitary method.
Time for 1 page = $\frac{40 \text{ minutes}}{2 \text{ pages}} = 20 \text{ minutes/page}$.
Step 2: Multiply the time per page by the total number of pages needed.
Time for 84 pages = $84 \times 20$.
Step 3: Solve the multiplication.
$84 \times 20 = 1680 \text{ minutes}$.

• Shortcut Method: The number of pages increases from 2 to 84, which is a multiplier of 42 (since $84 / 2 = 42$). Therefore, the time will also increase by a multiplier of 42. $40 \times 42 = 1680$ minutes.

• Final Answer: 1680

• Key Fact: The 'Digital India' campaign was officially launched by Prime Minister Narendra Modi on 1st July 2015.

• Supporting Detail: Its primary objective was to ensure that the Government's services are made available to citizens electronically by improved online infrastructure, expanding high-speed internet connectivity across rural areas, and making the country digitally empowered in the realm of technology.

• Why others wrong: While digital services expanded rapidly during the 2020 COVID-19 pandemic, the foundational umbrella scheme itself was launched much earlier in 2015.

• Exam Trick: Major flagship schemes of the NDA government like Make in India (2014) and Digital India (2015) were launched in the very first years of its initial term.

• Given conditions: COOK $\rightarrow$ 8245. HOOK $\rightarrow$ 5429.

• Deduction process:
Step 1: Identify the common letters between the two words. Both words end in 'OOK'. The common letters are O, O, and K.
Step 2: Identify the common digits in their respective codes. The codes are {8, 2, 4, 5} and {5, 4, 2, 9}. The common digits are 2, 4, and 5.
Step 3: This means the letters {O, O, K} are coded using the digits {2, 4, 5} in some jumbled order.
Step 4: Now look at the unique components. In 'HOOK', the unique letter is 'H'. In its code '5429', after removing the common digits {2, 4, 5}, the only digit left is 9.
Step 5: Therefore, 'H' must be coded as 9.

• Exam Trick: You don't need to find which number is exactly 'O' or 'K'. Just cancel out the shared parts (OOK = 2,4,5). The unique letter H directly maps to the unique remaining digit 9.

• Final Answer: 9

• Key Fact: The Kudankulam Nuclear Power Plant (KKNPP) in Tamil Nadu is the largest nuclear power station in India by installed capacity.

• Supporting Detail: Built in collaboration with Russia, it currently operates two VVER-1000 reactors, providing an operational capacity of 2000 MW, with several more reactors under construction to eventually reach a 6000 MW capacity.

• Why others wrong: Tarapur in Maharashtra was India's first commercial nuclear power station and is highly significant, but its current operational capacity is 1400 MW, making it second. Kakrapar (Gujarat) and Narora (UP) have smaller capacities (below 1200 MW).

• Exam Trick: Kudankulam = Largest capacity & Russian partnership. Tarapur = Oldest/First.

• Given conditions: 6 floors (1 is bottom, 6 is top). Fixed conditions: U=4. X is just below U. Two people between U and Z. T is strictly between U and Y.

• Deduction process:
1) 'U lives on floor number 4': U is fixed at 4.
2) 'X lives immediately below U': Therefore, X lives on floor 3.
3) 'Only two people live between U and Z': U is at 4. We need a gap of 2 floors. Since there are no floors 7 and 8 above U, Z must be below U. The floors between them would be 3 and 2. Therefore, Z lives on floor 1.
4) 'Only T lives between U and Y': U is at 4. This means U, T, Y must be contiguous (either U-T-Y or Y-T-U). Since 3 and 1 are already occupied by X and Z, Y and T cannot go downwards. They must go upwards to floors 5 and 6. For T to be exactly in the middle of U(4) and Y(6), T must live on floor 5.
5) The only remaining person is S, who must occupy the only remaining empty floor, which is floor 2.
Final arrangement (Top to Bottom): 6-Y, 5-T, 4-U, 3-X, 2-S, 1-Z.
Question asks: Who lives on floor number 5? It is T.

• Exam Trick: Lock the absolute given (U=4) and work upwards and downwards based on space constraints. U and Z having 2 gaps immediately forces Z to 1 because there is no floor 7.

• Final Answer: T

• Given: $f(x) = ax^2 + bx + c$. Leading coefficient $a = 1$. Remainder when divided by $(x-2)$ is 5. Remainder when divided by $(x-4)$ is -3.

• Basic Method (Solution):
Step 1: The polynomial is $f(x) = x^2 + bx + c$.
Step 2: By the Polynomial Remainder Theorem, dividing $f(x)$ by $(x - k)$ gives a remainder equal to $f(k)$.
Therefore, $f(2) = 5$ and $f(4) = -3$.
Step 3: Form the first equation using $x = 2$.
$f(2) = (2)^2 + 2b + c = 5 \implies 4 + 2b + c = 5 \implies 2b + c = 1$ --- (Eq 1)
Step 4: Form the second equation using $x = 4$.
$f(4) = (4)^2 + 4b + c = -3 \implies 16 + 4b + c = -3 \implies 4b + c = -19$ --- (Eq 2)
Step 5: Subtract Eq 1 from Eq 2 to eliminate $c$.
$(4b + c) - (2b + c) = -19 - 1$
$2b = -20 \implies b = -10$.
Step 6: Substitute $b = -10$ back into Eq 1.
$2(-10) + c = 1 \implies -20 + c = 1 \implies c = 21$.
Step 7: The polynomial is $f(x) = x^2 - 10x + 21$. The equation is $x^2 - 10x + 21 = 0$.

• Shortcut Method: Use the options and plug in $x=2$ and $x=4$ directly. The correct option must equal 5 when $x=2$ and equal -3 when $x=4$.
Test Option A ($x^2 - 10x + 21$):
For $x=2$: $2^2 - 10(2) + 21 = 4 - 20 + 21 = 5$. (Matches!).
For $x=4$: $4^2 - 10(4) + 21 = 16 - 40 + 21 = -3$. (Matches!).
No need to solve algebraically, Option A is instantly verified.

• Final Answer: $x^2-10x+21=0$

• Key Fact: Self-Help Groups (SHGs) in India are primarily informal associations of 10-20 individuals (overwhelmingly poor rural women) who come together to pool their small savings (thrift) and lend micro-credit to members internally at reasonable rates.

• Supporting Detail: SHGs form the backbone of the microfinance movement in India (such as the NABARD SHG-Bank Linkage Programme) empowering women financially and socially without needing complex collateral.

• Why others wrong: They do not provide 'large-scale industrial loans', they are completely informal and private (not 'government-owned cooperative banks'), and they have no institutional relation to being RBI regional offices.

• Exam Trick: SHG = Small Savings + Micro-credit + Rural Women Empowerment.