RRB NTPC CBT 1 2016: questions with answers

A moth belongs to the class of insects; a mouse belongs to the group of rodents (gnawing mammals).

ILOLSGNH = SHILLONG, OHALPB = BHOPAL and ENANCIH = CHENNAI are state capitals. UNPE = PUNE is not a state capital, so it is the odd one.

The loudness (sound intensity level) of sound is measured in decibels (dB), named after Alexander Graham Bell.

Coefficient of variation = (standard deviation ÷ mean) × 100 = 5/10 × 100 = 50%.

Sum of 15 observations = 15 × 14 = 210. Sum of 18 observations = 18 × 13 = 234. The three new observations total 24, so their mean is 8.

WWW stands for the World Wide Web, the system of linked web pages accessed over the Internet.

A convex mirror gives an erect, diminished image and a wide field of view, so it is used as the rear-view mirror in vehicles.

Replacing the letters: 10 − 5 × 27 ÷ 9 + 10 = 10 − 15 + 10 = 5.

Take the original price as 100. After the first owner's 10% profit it is 110; after the second's 30% it is 143. The final price is 150, so the third owner's profit = 7/143 × 100 ≈ 4.9%.

Write LEADER backwards (REDAEL) and shift the letters −3, −3, −3, +3, +3, +3: R→O, E→B, D→A, A→D, E→H, L→O = OBADHO. STABLE backwards is ELBATS: E→B, L→I, B→Y, A→D, T→W, S→V = BIYDWV.

Let Mayank invest 5k; then Sakshi invests 3k and Suman 15k. Ratio Suman : Sakshi : Mayank = 15 : 3 : 5 (23 parts). Sakshi's share = 3/23 × 23,000 = Rs 3,000.

Supplementary angles add up to 180°. 13 : 5 means 18 parts = 180°, so 1 part = 10°: the angles are 130° and 50°, and their difference is 80°.

'Black Beauty' (NWA 7034) is a dark, coal-coloured meteorite from Mars found in the Sahara in 2011; it is one of the oldest known Martian rocks.

At Independence in 1947 Goa was still a Portuguese colony; it was liberated by Operation Vijay in December 1961.

Lonar Lake in Buldhana district, Maharashtra, is a saline soda lake that fills a crater formed by a meteorite impact about 50,000 years ago.

Variance = (standard deviation)² = 8² = 64.

x² − 4x + 1 = 0 gives x + 1/x = 4. Then x² + 1/x² = 16 − 2 = 14 and x³ + 1/x³ = 4³ − 3 × 4 = 52. The ratio is 52/14 = 26/7.

Satya Nadella replaced Steve Ballmer as CEO of Microsoft in February 2014.

8¹⁰ = 2³⁰, 9⁷ = 3¹⁴ and 7⁸ = 7⁸. The total number of prime factors is 30 + 14 + 8 = 52.

The numbers are 2 × 45, 3 × 45 and 6 × 45 = 90, 135 and 270. Their sum is 11 × 45 = 495.

Jaipur, Rajasthan's capital, is called the Pink City because its old city buildings were painted pink (terracotta) in 1876 to welcome the Prince of Wales.

Bangladesh (formerly East Pakistan) won independence from Pakistan in the 1971 Liberation War; Pakistan surrendered on 16 December 1971.

Two distinct straight lines can meet in at most one point, so statement 1 is false. If the arms of two angles are parallel in pairs, the angles are either equal or supplementary, so statement 2 is true.

1.93 × 19.3 = 37.249 and 2.07 × 20.7 = 42.849. Their difference is −5.6, and 19.3 − 20.7 = −1.4. −5.6 ÷ −1.4 = 4.

All mangoes are golden and no golden thing is cheap, so no mango is cheap: golden mangoes are not cheap (2 follows), and 1 is the opposite of what follows.

OLENV = NOVEL, AGZEANIM = MAGAZINE and TCAYRIDION = DICTIONARY are kinds of books. EISTSH = THESIS is the odd one, as per the official key.

Total goals scored equal total goals conceded: 2 + 3 + Chennai = 4 + 7 + 1 = 12, so Chennai scored 7 goals.

Delhi drew one match. If Delhi–Mumbai were the draw at y–y, Chennai would concede (2 − y) + (3 − y) = 1, so y = 2. Then Delhi lost 0–2 to Chennai, and Mumbai, conceding 7 in all, lost 1–5 to Chennai.

The results work out as Delhi 2–2 Mumbai, Chennai 2–0 Delhi and Chennai 5–1 Mumbai. Mumbai lost one match.

Let the second number be s. Then the first is s/3 and the third is s/2. Sum = s(1/3 + 1 + 1/2) = 11s/6 = 3 × 77 = 231, so s = 126.

In a sugar solution, sugar is the solute (the substance dissolved) and water is the solvent.

Q does 5/6 of the work in 15 days, so Q alone takes 18 days. Together they do half the work in 45/8 days, i.e. the whole in 45/4 days: 1/X + 1/18 = 4/45, so 1/X = 3/90 and X = 30.

A prism refracts (bends) light passing through it; because different colours bend by different amounts, it also disperses white light into a spectrum.

World Cancer Day is observed on 4 February each year, led by the Union for International Cancer Control (UICC).

Carbon monoxide binds to haemoglobin about 200 times more strongly than oxygen, forming carboxyhaemoglobin, so the blood cannot carry oxygen and inhaling it can kill. Both A and R are true and R explains A.

Hafnium (Hf) is named after Hafnia, the Latin name of Copenhagen, where it was discovered in 1923.

In February 2015 the MCC (Lord's) awarded honorary life membership to Sourav Ganguly in recognition of his contribution to cricket. (M. S. Dhoni received it only in 2023.)

Alfred Nobel invented dynamite in 1867; his fortune from it funds the Nobel Prizes.

Sapphire (neelam), ruby (manik) and emerald (panna) are all gems (ratna), so 'Ratna' is the class.

The Supreme Court of India was inaugurated on 28 January 1950, two days after the Constitution came into force.

Tiruppur Kumaran, the freedom fighter who died in 1932 holding the national flag during a protest march, founded the Desa Bandhu Youth Association.

The sum becomes 5 times, so the interest is 4 times the principal in 10 years: 400% in 10 years, or 40% per annum.

The kidneys filter the blood, removing urea and other wastes, which leave the body as urine.

Cochin International Airport, Kerala, became the world's first airport fully powered by solar energy in August 2015.

Let 3^x = 4^y = 12^(−z) = k. Then 3 = k^(1/x), 4 = k^(1/y) and 12 = k^(−1/z). Since 3 × 4 = 12, 1/x + 1/y = −1/z, so 1/x + 1/y + 1/z = 0 and the expression is 0.

Only English = 2400 − 1000 − 500 + 100 = 1000; only Telugu = 1700 − 1000 − 300 + 100 = 500; only Hindi = 800 − 500 − 300 + 100 = 100. Total knowing exactly one language = 1600.

Only Hindi = 800 − (500 + 300) + 100 = 100.

All 3200 students know at least one language (2400 + 1700 + 800 − 1000 − 500 − 300 + 100 = 3200), so none knows none of them.

9 cos A + 12 sin A = 15 means 3 cos A + 4 sin A = 5, the maximum value, reached when cos A = 3/5 and sin A = 4/5. So cot A = 3/4.

Tiger Woods is the American golfer with 15 major titles. Danny Brooks is a British racing driver, and Scott Henderson and Nick Flanagan are not American golf stars.

X = HCF × LCM ÷ 207 = 23 × 1035/207 = 115. X/23 = 5.

'Delicious' describes a pleasing taste; 'melodious' describes a pleasing voice (sound).

Let the younger be x and the elder x + 12. Nine years ago: x + 3 = 4(x − 9), so x = 13. Their ages are 13 and 25.

For the same distance, time is inversely proportional to speed: 1/10 : 1/3 : 1/20 = 6 : 20 : 3.

1 is paired with 1² = 1, so 25 is paired with 25² = 625.

Cristiano Ronaldo plays for and captains Portugal; he led them to the Euro 2016 title.

Ancient civilisations grew near rivers for water, fertile soil and transport, and agriculture was indeed the main occupation. The official key treats both as true but R as not the proper explanation of A.

Charu, the unmarried only child whose grandparents are dead, is in the last (6th) generation, and Charu's parent is in the 5th. The grandparents, who are dead, belong to the 4th generation, i.e. second from last.

With Aditya (5th generation) as Charu's father and grandson of Bawan, Bawan is in the 3rd generation, and Varun and his daughter Deepa occupy generations 1 and 2. The official key counts 4 possible combinations of these family links.

If Aditya is Bawan's grandson, Aditya is in the 5th generation as Charu's parent, so the member just before the last generation is Aditya.

SP = Rs 600 at 20% profit gives CP = Rs 500. SP is 60% of the marked price, so MP = 1000. Selling at MP gives a profit of 500 on 500 = 100%.

By alligation: (60 − 40) : (40 − 30) = 20 : 10 = 2 : 1 (30% solution : 60% solution).

The Great Pyramid of Khufu (Cheops) at Giza is the largest Egyptian pyramid, originally about 146.6 m tall.

Palam is Delhi's airport; Dum Dum is the airport of Kolkata (Netaji Subhas Chandra Bose International).

Sumitra Mahajan, Lok Sabha Speaker from 2014 to 2019, represented Indore (Madhya Pradesh) for eight terms.

The control unit directs and coordinates all parts of the computer, like the nervous system, so it is called the nerve centre (with the CPU).

A car, van and taxi are four-wheelers; an auto-rickshaw has three wheels, so it is the odd one.

From BEND = 7@4#: B 7, E @, D #. From NIGHT = 4$%89: T 9. DEBT = # @ 7 9.

The density of water is about 1000 kg/m³ (1 g/cm³), maximum at 4 °C.

Replacing the signs: 15 × 16 ÷ 16 − 15 = 15 − 15 = 0.

B does 6/100 of the work per day. Together they finish the remaining 3/5 in 6 days, so A + B = 1/10 a day and A = 1/10 − 6/100 = 1/25. A does 2/5 of the work in (2/5) × 25 = 10 days.

A person stands on the floor, and in this code the floor is called the roof.

Gregor Mendel, through pea-plant experiments (1856–63), proposed the laws of heredity; he is the father of genetics.

P. K. Nair, founder-director of the National Film Archive of India who saved many early Indian films, was called the 'Celluloid Man'; he died in March 2016.

Gyroscopic (air) mice use a gyroscope to track movement in the air, so the official key marks the computer mouse.

A number is divisible by 11 if the difference between the sums of alternate digits is a multiple of 11. For 49231754: (4 + 2 + 1 + 5) − (9 + 3 + 7 + 4) = 12 − 23 = −11, so it is divisible by 11.

Bakhtiyar Khilji attacked Nadia around 1203–04 and defeated Lakshmana Sena of the Sena dynasty of Bengal.

With angles in the ratio 2 : 3 : 7, (largest + smallest) : smallest = (7 + 2) : 2 = 9 : 2.

Let CP = C and profit = p. Doubling SP gives 2(C + p) − C = 4p, so C = 2p. The original profit percent = p/C × 100 = 50%.

Snails are molluscs (phylum Mollusca), with soft bodies and usually a shell. Cockroaches are arthropods, earthworms annelids and starfish echinoderms.

2x² − 5x + 2 = (2x − 1)(x − 2), so x − 2 is a factor.

The early Cheras, one of the three Sangam-age dynasties, ruled the Malabar coast, today's Kerala and parts of western Tamil Nadu.

'Making India Awesome' (2015) is a collection of essays by novelist Chetan Bhagat.

'Straight Drive' (1984) is a book by Sunil Gavaskar; his other books include 'Sunny Days' and 'Idols'.

Netrani (Pigeon) Island lies in the Arabian Sea off Murudeshwar in Uttara Kannada district, Karnataka, and is known for coral reefs and scuba diving. (The official sheet lists Lakshadweep for this option, but the island is in Karnataka.)

Liu Yang became the first Chinese woman in space aboard Shenzhou 9 in June 2012.

The interest for 3 years (years 5–7) is 1500 − 1200 = Rs 300, i.e. Rs 100 a year. For 4 years it is Rs 400, so the principal is 1200 − 400 = Rs 800.

O-group blood has no A or B antigens, so it can be given to anyone: O is the universal donor, not recipient (AB is the universal recipient). A is false and R is true.

Speed = distance/time. The person covers 1/3 the distance in 3 times the time, so the speed ratio is (1/3)/3 = 1/9: 1 : 9.

The Chennakeshava temple at Belur, Karnataka, was built in 1117 by the Hoysala king Vishnuvardhana.

Scurvy (bleeding gums, poor wound healing) is caused by a deficiency of vitamin C (ascorbic acid), found in citrus fruits and amla.

Dry ice is solid carbon dioxide; it sublimes at −78.5 °C without melting and is used for cooling and stage fog.

27 = 3³ and 9 = 3², so the first number is the cube and the second the square of the same base. 729 = 9³ and 81 = 9², so 729 : 81 matches.

Replacing the letters: 44 + 64 − 60 ÷ 15 × 4 = 108 − 16 = 92.

Adding A + B = 2C and C + D = 2A gives A + B + C + D = 2A + 2C, so B + D = A + C.

Salt lowers the freezing point of water, so spreading salt on ice makes it melt at temperatures below 0 °C; it is used to clear icy roads.

MIPS stands for Million Instructions Per Second, a measure of a processor's speed.

From CHAIR = $∗1÷8: A 1, R 8. From HIDE = ∗÷35: D 3, E 5. DEAR = 3 5 1 8.

Let the height be h. The shadow at 30° is h√3 and at 60° it is h/√3. The difference h(√3 − 1/√3) = 2h/√3 = 24, so h = 12√3 m.

Girls = 11/24 × 504 = 231 and boys = 273. With 12 more girls: 243 : 273 = 81 : 91.