Q&A: practice questions with answers

Concept: Tippani is a women's folk dance of the Chorwad (Saurashtra) region of Gujarat.

1. It came from labourers ramming lime-and-concrete floors.
2. The 'tippani' is a long wooden stick with a block at the end, used to pound the floor in rhythm with songs.

Yaad rakhein: Tippani = the stick itself – so the tool is wooden sticks.

Answer: (C) Wooden sticks

Concept: The yearly World Competitiveness Yearbook/Ranking is published by IMD, Lausanne.

1. IMD = International Institute for Management Development, a Swiss business school.
2. Its World Competitiveness Center ranks economies on four pillars: economic performance, government efficiency, business efficiency, infrastructure.

Yaad rakhein: Don't confuse with WEF's Global Competitiveness Report (Geneva-based forum).

Answer: (A) IMD Business School

Concept: Ed = % change in quantity demanded ÷ % change in price.

1. Ed = 20% ÷ 10% = 2.
2. Since 2 > 1, demand is relatively elastic.

Trick: Quantity changes MORE than price → elastic; LESS → inelastic; EQUAL → unitary.

Answer: (B) Elastic demand (elasticity > 1)

Concept: P.C. Mahalanobis's model was the base of the Second Five-Year Plan (1956–61).

1. Focus: rapid industrialisation through heavy and basic industries in the public sector.
2. First Plan (1951–56) used the Harrod–Domar model and prioritised agriculture.

Yaad rakhein: 1st = Harrod–Domar (agriculture), 2nd = Mahalanobis (industry).

Answer: (A) Second Five-Year Plan

Concept: The 2025 scheme that ties mangrove restoration to MGNREGS wage work is Mission Mangrove Mitra.

1. Villagers are hired under MGNREGS to plant, protect and maintain mangroves as 'Mangrove Mitras'.
2. It complements MISHTI (Mangrove Initiative for Shoreline Habitats & Tangible Incomes, 2023).

Yaad rakhein: The word 'Mitra' (friend) signals community participation – a giveaway among the invented-sounding names.

Answer: (B) Mission Mangrove Mitra

Concept: A BoP crisis means the country cannot pay for imports/debt – i.e., a shortage of foreign exchange.

1. Reserves fell to barely enough for about two weeks of imports.
2. Gulf War oil price shock, fall in remittances and high external debt deepened it.
3. India pledged gold and took IMF help, leading to LPG reforms.

Yaad rakhein: 'Balance of Payments' always relates to foreign currency – eliminates food, goods and savings.

Answer: (B) Foreign exchange

Concept: Judge A and R separately, then ask: 'Is A true BECAUSE of R?'

1. A ✓ – India borrowed from the IMF and World Bank in 1991.
2. R ✓ – reserves had shrunk to about two weeks' import cover.
3. Low reserves are exactly why the loan was needed → R explains A.

Trick: Put 'because' between A and R: 'India sought a loan because reserves covered only 2 weeks' – reads right.

Answer: (A) Both A and R are true, and R explains A.

Concept: 'Syncretic' = mixing several traditions; Chhau mixes tribal, folk, martial and classical Hindu elements.

1. Found in Odisha (Mayurbhanj), Jharkhand (Seraikela) and West Bengal (Purulia).
2. Stories come from the Ramayana, Mahabharata and Puranas; movements draw on martial and tribal practices; Purulia and Seraikela styles use masks.
3. UNESCO Intangible Cultural Heritage list – 2010.

Trick: Syncretic = blend; only option (A) talks about blending.

Answer: (A) It blends tribal, folk, and classical Hindu cultural traits

Concept: Place each case by its year of judgement.

1. Berubari Union – 1960 (Preamble not part of the Constitution; ceding territory needs an amendment).
2. Minerva Mills – 1980 (basic structure; balance of FRs and DPSPs).
3. Indra Sawhney – 1992 (OBC reservation, 50% cap, creamy layer).
4. Order: 1 → 3 → 2.

Trick: Mandal case (Indra Sawhney) came after the 1990 Mandal implementation – so it must be last.

Answer: (A) 1-3-2

Concept: Solar flares and CMEs disturb Earth's ionosphere and magnetosphere.

1. X-rays and charged particles ionise the upper atmosphere → HF radio blackouts, GPS errors, satellite and power-grid trouble, auroras.
2. Ocean currents and volcanoes are driven by processes on/inside Earth, not by the Sun's outbursts.

Trick: Space weather hits 'signals and electricity' – radio, GPS, satellites, grids.

Answer: (B) Radio signal blackouts

Concept: Trees in a square = $n^2$, where n = trees per row.

1. Trees used = $4112-16=4096$.
2. $n^2=4096\to n=\sqrt{4096}=64$.

Trick: $4096=2^{12}$ → √ $=2^6=64$. Or: unit digit 6 → root ends in 4 or 6; ${64}^2=4096$.

Answer: (C) 64

Concept: Convert each % into a ratio and chain them.

1. Q is 20% more than R → R : Q = 5 : 6.
2. P is 25% more than Q → Q : P = 4 : 5.
3. $\frac{P}{R}=(\frac{6}{5})\times (\frac{5}{4})=\frac{6}{4}=\frac{3}{2}\to P:R=3:2$.

Trick: Multiply the factors: $1.2\times 1.25=1.5=\frac{3}{2}$.

Answer: (A) 3 : 2

Concept: For $\sqrt{n+\sqrt{n+\sqrt{n+\dots }}}$, let x = value; then $x^2=n+x$.

1. $x^2-x-30=0$.
2. $(x-6)(x+5)=0\to x=6$ (value must be positive).

Trick: Split n as $k(k+1)$: $30=5\times 6$. With '+' signs take the larger factor (6); with '−' signs take the smaller.

Answer: (D) 6

Concept: $\text{SP}=\text{MP}\times \frac{100-d}{100}$; profit% is on CP.

1. $\text{SP}=400\times \frac{80}{100}=$ ₹320.
2. Profit = $320-200=$ ₹120.
3. Profit% = $\frac{120}{200}\times 100=60\%$.

Trick: MP is $2\times \text{CP}$; 80% of 2 = 1.6 → 60% profit straight away.

Answer: (A) 60% Profit

Concept: Use LCM as tank capacity; outlet's rate is subtracted.

1. Capacity = $\text{LCM}(15,30,60)=60$ units.
2. $A=\frac{60}{15}=4,B=\frac{60}{30}=2,C=-\frac{60}{60}=-1$ unit/min.
3. Net = 5 units/min → time = $60÷5=12$ min.

Trick: Combined time must be less than A's 15 min alone – only 12 and 10 qualify; check 12.

Answer: (A) 12 min

Concept: If $x+y+z=0$, then $x^3+y^3+z^3=3xyz$.

1. Take $x=a-b,y=b-c,z=c-a$.
2. $x+y+z=a-b+b-c+c-a=0$.
3. So the sum of cubes = $3(a-b)(b-c)(c-a)$.

Trick: Spot that the three brackets cancel out – then apply $3xyz$ directly, no expansion.

Answer: (D) 3(a − b)(b − c)(c − a)

Concept: Let the part at 6% be x; total yearly interest = ₹630.

1. $6\%$ of $x$ + $9\%$ of $(9000-x)=630$.
2. $0.06x+810-0.09x=630\to 0.03x=180$.
3. x = ₹6000.

Trick: Average rate = $\frac{630}{9000}=7\%$. Distance from 9 is 2, from 6 is 1 → shares 2 : 1 → 6% part = $\frac{2}{3}\times 9000$.

Answer: (A) ₹6000

Concept: Let Asha get x; $\text{SI}=\frac{P\times R\times T}{100}$.

1. Asha: $\frac{x\times 10\times 3}{100}=0.3x$; Meena: $\frac{(15000-x)\times 12\times 3}{100}=0.36(15000-x)$.
2. $0.3x+5400-0.36x=4950\to 0.06x=450$.
3. $x=$ ₹7,500.

Trick: Average rate = $4950÷3÷15000=11\%$, exactly midway between 10% and 12% → equal halves.

Answer: (B) ₹7,500

Concept: Ground distance is adjacent to the 60° angle; cable is the hypotenuse → use cos.

1. $\cos {60}^{\circ }=\frac{\text{base}}{\text{cable}}\to \frac{1}{2}=\frac{20}{\text{cable}}$.
2. Cable = 40 m.

Trick: In a 30-60-90 triangle the side next to 60° is half the hypotenuse.

Answer: (C) 40 m

Concept: Equate $\frac{1}{3}\pi R^{2}h$ with $\frac{4}{3}\pi r^3$.

1. $h=3R\to \text{cone volume}=\frac{1}{3}\pi R^2\times 3R=\pi R^3$.
2. $\pi R^3=\frac{4}{3}\pi r^3\to \frac{R^3}{r^3}=\frac{4}{3}$.
3. $R:r=\sqrt[3]{4}:\sqrt[3]{3}$.

Trick: Cone with $h=3R$ has volume exactly $\pi R^3$ – remember it.

Answer: (B) ∛4 : ∛3