Q&A: practice questions with answers

Concept: Options of the Governor on a State Bill.

1. Under Article 200 the Governor may give assent, withhold assent, return it (non-money Bill), or reserve it for the President.
2. The President decides on reserved Bills under Article 201.

Yaad rakhein: Remember the pair: Art. 200 (Governor) → Art. 201 (President on reserved Bills).

Answer: (C) President

Concept: In β⁺ decay a proton changes into a neutron, emitting a positron (and a neutrino).

1. Protons fall by 1 → atomic number Z − 1.
2. Neutrons rise by 1, so total nucleons stay same → mass number A unchanged.
3. (B) is β⁻ decay; (D) is α decay.

Trick: β⁺: Z − 1; β⁻: Z + 1; α: Z − 2, A − 4; γ: no change in Z or A.

Answer: (A) Proton number decreases by 1 while the mass number remains unchanged

Concept: Key trend reported by the World Economic Forum's ETI 2025.

1. The report notes global energy demand is still rising, pushed by electrification and higher cooling needs.
2. It flags transition investment and readiness as lagging, not above average – (C) wrong; AI is adding to demand, not reducing it – (D) wrong.

Yaad rakhein: Sweden has topped the ETI ranking for several years; the index is published by WEF (Geneva).

Answer: (A) Demand continues to rise because of electrification and cooling needs

Concept: Origin of Ghoomar and India's UNESCO intangible heritage list.

1. Ghoomar began in the Bhil tribe and was later adopted by Rajput communities of Rajasthan – A is correct.
2. Ghoomar is NOT on UNESCO's Intangible Cultural Heritage list – R is incorrect.

Yaad rakhein: Rajasthan's dance on the UNESCO list is Kalbelia (2010), not Ghoomar.

Answer: (B) A is correct, but R is incorrect

Concept: Capital receipt = creates a liability or reduces an asset of the government.

1. A loan from the RBI must be repaid → creates liability → capital receipt.
2. Income tax, PSU dividends and service charges create no liability → revenue receipts.

Trick: Ask 'Will the government owe it back or lose an asset?' Yes → capital (borrowings, loan recovery, disinvestment).

Answer: (C) Loan raised from the Reserve Bank of India (RBI)

Concept: Swadeshi enterprises set up to challenge British business.

1. In 1906 V.O.C. founded the Swadeshi Steam Navigation Company at Tuticorin (Thoothukudi).
2. Its ships ran between Tuticorin and Colombo, against the British India Steam Navigation Company's monopoly.

Trick: 'Kappalottiya Thamizhan' = 'the Tamil who sailed ships' – the title itself points to shipping.

Answer: (B) Swadeshi Steam Navigation Company

Concept: Democratic planning invites and uses feedback.

1. Draft plans are circulated to ministries, states, experts and the public.
2. Their criticism and suggestions are used to revise the draft before final approval.
3. Options A, B and D describe ignoring feedback – the opposite of responsiveness.

Trick: Words like 'ignoring', 'only foreign', 'before any opinion' are extreme – eliminate them.

Answer: (C) By revising plan drafts based on criticism and recommendations received

Concept: Personalities behind India's agricultural revolutions.

1. Verghese Kurien led Operation Flood (from 1970) through NDDB, building the Amul cooperative model nationwide.
2. It made India the world's largest milk producer; he is called the Father of the White Revolution.
3. He did not invent pasteurisation – (C) wrong.

Yaad rakhein: 26 November (Kurien's birthday) is observed as National Milk Day.

Answer: (B) He pioneered Operation Flood, transforming India's dairy industry

Concept: Cities become warmer than nearby rural areas due to man-made surfaces and heat.

1. Concrete, asphalt and buildings store solar heat in daytime and give it back after sunset, keeping nights warm.
2. Vehicles, ACs and industries add waste heat; few trees/water bodies means less cooling.
3. Trees and lakes cool the air, so (B) is wrong.

Yaad rakhein: UHI fix = more green cover, cool/white roofs, water bodies.

Answer: (C) Because concrete infrastructure and vehicles release and retain heat while greenery is limited

Concept: 101st Amendment (2016) added Articles 246A and 279A.

1. Art. 246A gives BOTH Parliament and State Legislatures power to make GST laws (concurrent) – statement 1 wrong.
2. So States can legislate on intra-state GST (SGST) – statement 2 wrong.
3. Art. 279A creates the GST Council, a constitutional body – statement 3 correct.

Trick: GST is 'dual GST' – Centre (CGST) + State (SGST); the word 'exclusive' in statement 1 is the red flag.

Answer: (C) 3 only

Concept: $A=P(1+\frac{r}{100}{)}^n$.

1. $20\%=\frac{1}{5}$, so each year the multiplier is $\frac{6}{5}=1.2$.
2. ${1.2}^5=1.44\times 1.44\times 1.2=2.48832$.
3. $A=4000\times 2.48832=$ ₹9,953.28 $\approx$ ₹9,953.2.

Trick: Only (C) is close to $4000\times 2.5=10,000$ from below – pick it without full multiplication.

Answer: (C) ₹9,953.2

Concept: $\frac{p}{q}$ (lowest terms) terminates only if q has no prime factor other than 2 and 5.

1. $\frac{7}{5}$: denominator 5 → $\frac{7}{5}=1.4$, terminates ✓
2. $\frac{2}{3}$: denominator 3 → $0.666\dots$ recurring.
3. $\sqrt{5}$ and $\pi$ are irrational – not rational at all.

Trick: Look only at the denominator: made of 2s and 5s → terminating.

Answer: (B) $\frac{7}{5}$

Concept: Average speed = total distance ÷ total time (not the average of speeds).

1. Time-1 = $\frac{12}{10}=\frac{6}{5}$ h; time-2 = $\frac{16}{12}=\frac{4}{3}$ h.
2. Total time = $\frac{6}{5}+\frac{4}{3}=\frac{38}{15}$ h; distance = 28 km.
3. Speed = $28\times \frac{15}{38}=\frac{420}{38}\approx 11.05$ km/h.

Trick: Answer must lie between 10 and 12 (strictly) – only 11.05 fits.

Answer: (D) 11.05 km/h

Concept: $V\propto r^3$, so the given $288\pi$ is not needed.

1. New r = $3r$ → new V = 27 × old V.
2. Increase = $27-1=26$ times the old volume.
3. % increase = $26\times 100=2600\%$.

Trick: % increase when a length becomes k times: $(k^3-1)\times 100\%$ for volume.

Answer: (B) 2600%

Concept: Area = length × breadth.

1. $15.75\times 8=126$; $15.75\times 0.2=3.15$.
2. Area = $126+3.15=129.15$ m².

Trick: Unit digit check: $5\times 2$ ends in 0 and there are 3 decimal places → result ends '…150' → 129.15.

Answer: (A) 129.15 m²

Concept: Servings are directly proportional to milk.

1. $4.25÷0.85=425÷85=5$ → milk is 5 times.
2. Servings = $15\times 5=75$.

Trick: Spot that $85\times 5=425$ – no need to find milk per serving.

Answer: (D) 75

Concept: Profit is shared in the ratio of capital × time.

1. Let each invest x. D: $12x+15000\times 6=12x+90,000$; E: $12x$.
2. D's profit = $35,000-10,000=25,000$ → D : E = 5 : 2.
3. $2(12x+90,000)=5\times 12x\to 36x=1,80,000\to x=$ ₹5,000.

Trick: Option check: $x=5000$ → D = 1,50,000, E = 60,000 → 5 : 2 ✓.

Answer: (C) ₹5,000

Concept: When x : y is given, put x = 3, y = 7 directly.

1. 2x + 3y = 6 + 21 = 27.
2. x + y = 10.
3. Required ratio = 27 : 10.

Trick: Expression ratios are homogeneous (degree 1), so plugging the ratio numbers always works.

Answer: (A) 27 : 10

Concept: Form the equation and factorise.

1. $x^2-5x=150\to x^2-5x-150=0$.
2. $(x-15)(x+10)=0\to x=15$ (or −10).
3. Among the options, 15.

Trick: Option test: ${15}^2-5\times 15=225-75=150$ ✓ – faster than solving.

Answer: (B) 15

Concept: Area $=\frac{1}{2}|x_1(y_2-y_3)+x_2(y_3-y_1)+x_3(y_1-y_2)|$.

1. $4(2-12)=-40$; $14(12-6)=84$; $8(6-2)=32$.
2. Sum = 76.
3. Area $=\frac{76}{2}=38$ sq units.

Trick: Shift origin to A: B(10, −4), C(4, 6) → $\frac{1}{2}|10\times 6-(-4)\times 4|=\frac{1}{2}\times 76=38$.

Answer: (B) 38 square units