TCS NQT Practice — Set 1

25 NQT-pattern questions across numerical ability, reasoning, verbal and programming logic — the four sections every TCS aspirant faces.

Quantitative Aptitude25 questionsInstant feedback + explanationsup to ≈150 XP

One question at a time — answer, learn from the explanation, and keep your combo alive. Stuck? You have two 50:50s and one hint (each halves that question's XP).

Practice sheet: all 25 questions

Prefer reading first? Every question from this practice set, with the answer and a worked explanation. (Solving them in the practice set above earns XP — up to ≈150.)

Q1. What is the unit digit of 7^63?
- a. 1
- b. 3
- c. 7
- d. 9
Show answer & explanation

Answer: B. 3

Unit digits of powers of 7 cycle with period 4: 7, 9, 3, 1. Since 63 = 4×15 + 3, the unit digit is the 3rd in the cycle — 3. NQT loves cyclicity questions: memorise the cycles of 2, 3, 7 and 8.
Q2. A student scores 72 marks out of 120. What percentage did the student score?
- a. 55%
- b. 58%
- c. 60%
- d. 64%
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Answer: C. 60%

72 ÷ 120 × 100 = 60%. A quick route: 120 × 0.6 = 72, so the answer is exactly 60%. Scaling the denominator to 100 (here ×5/6) is often faster than long division.
Q3. ₹1,800 is divided between A and B in the ratio 4 : 5. How much does B receive?
- a. ₹800
- b. ₹900
- c. ₹1,000
- d. ₹1,100
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Answer: C. ₹1,000

Total parts = 4 + 5 = 9, so one part = 1800 ÷ 9 = ₹200. B gets 5 parts = ₹1,000. Always sanity-check that both shares add back to the total: 800 + 1000 = 1800. ✓
Q4. A can finish a job in 12 days and B in 18 days. Working together, how many days do they take?
- a. 6.8 days
- b. 7.2 days
- c. 7.5 days
- d. 8 days
Show answer & explanation

Answer: B. 7.2 days

Take LCM(12, 18) = 36 units of work. A does 3 units/day, B does 2 units/day, together 5 units/day → 36 ÷ 5 = 7.2 days. The LCM method avoids fractions and is the standard trick for every time-and-work question.
Q5. A 240 m long train crosses a pole in 12 seconds. What is its speed in km/h?
- a. 60 km/h
- b. 66 km/h
- c. 72 km/h
- d. 80 km/h
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Answer: C. 72 km/h

Crossing a pole means covering its own length: speed = 240 ÷ 12 = 20 m/s. Convert with the ×18/5 factor: 20 × 18/5 = 72 km/h. Memorise both directions: m/s → km/h is ×18/5, km/h → m/s is ×5/18.
Q6. A shopkeeper buys an article for ₹480 and sells it at a 15% profit. What is the selling price?
- a. ₹540
- b. ₹546
- c. ₹552
- d. ₹560
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Answer: C. ₹552

Selling price = 480 × 1.15 = ₹552. Splitting helps mental math: 10% of 480 is 48 and 5% is 24, so the profit is 48 + 24 = ₹72, giving 480 + 72 = 552.
Q7. The average of 5 numbers is 42. If the number 58 is removed, what is the average of the remaining 4 numbers?
- a. 36
- b. 38
- c. 40
- d. 41
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Answer: B. 38

Total of 5 numbers = 5 × 42 = 210. Removing 58 leaves 210 − 58 = 152, and 152 ÷ 4 = 38. Working with totals instead of averages is the key move in every averages question.
Q8. What is the simple interest on ₹6,000 at 8% per annum for 3 years?
- a. ₹1,240
- b. ₹1,380
- c. ₹1,440
- d. ₹1,520
Show answer & explanation

Answer: C. ₹1,440

SI = P × R × T ÷ 100 = 6000 × 8 × 3 ÷ 100 = ₹1,440. Simple interest is linear — 8% of 6,000 is 480 per year, so 3 years is just 3 × 480.
Q9. The sides of a rectangle are in the ratio 3 : 2 and its perimeter is 60 cm. What is its area?
- a. 200 cm²
- b. 216 cm²
- c. 224 cm²
- d. 240 cm²
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Answer: B. 216 cm²

Let the sides be 3x and 2x. Perimeter 2(3x + 2x) = 10x = 60, so x = 6 — sides are 18 cm and 12 cm. Area = 18 × 12 = 216 cm². Convert ratio to actual lengths first; never multiply ratio numbers directly.
Q10. What is the smallest number that leaves a remainder of 3 when divided by 4, 5 and 6?

Show answer & explanation

Answer: 63

A number leaving the same remainder 3 with each divisor is LCM(4, 5, 6) + 3. LCM(4, 5, 6) = 60, so the answer is 63. Check: 63 = 15×4+3 = 12×5+3 = 10×6+3. ✓
Q11. Find the next term: 3, 7, 15, 31, 63, ?
- a. 95
- b. 123
- c. 127
- d. 131
Show answer & explanation

Answer: C. 127

Each term is double the previous plus 1: 63 × 2 + 1 = 127. Equivalently every term is 2ⁿ − 1 (4, 8, 16, 32, 64, 128 minus one). Checking differences (4, 8, 16, 32 — doubling) reveals the pattern fastest.
Q12. In a certain code, CAT is written as DBU. How is DOG written in the same code?
- a. EPH
- b. EPI
- c. FPH
- d. EQH
Show answer & explanation

Answer: A. EPH

Each letter moves one step forward: C→D, A→B, T→U. Applying +1 to DOG gives E, P, H → EPH. In coding questions, always compute the letter-shift from the given pair before touching the target word.
Q13. Pointing to a photograph, Ravi says, "She is the daughter of my grandfather's only son." How is the woman related to Ravi?
- a. Cousin
- b. Sister
- c. Aunt
- d. Mother
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Answer: B. Sister

My grandfather's only son must be Ravi's own father. The daughter of Ravi's father is Ravi's sister. Break blood-relation chains from the inside out — resolve "grandfather's only son" first, then attach the rest.
Q14. A man walks 5 km north, turns right and walks 3 km, then turns right again and walks 5 km. How far is he from the starting point?
- a. 3 km
- b. 5 km
- c. 8 km
- d. 13 km
Show answer & explanation

Answer: A. 3 km

The two 5 km legs are in opposite directions (north, then south after two right turns) and cancel out, leaving only the 3 km eastward leg. Sketching the path takes ten seconds and makes direction questions error-proof.
Q15. Statements: All pens are books. Some books are copies. Conclusions: I. Some pens are copies. II. Some copies are books. Which conclusion(s) follow?
- a. Only I follows
- b. Only II follows
- c. Both I and II follow
- d. Neither follows
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Answer: B. Only II follows

II is just the converse of "some books are copies", which is always valid. I does not follow — the copies could be exactly the books that are not pens. When a syllogism mixes "all" and "some", draw a Venn diagram where the "some" overlap avoids the smaller set.
Q16. Choose the word closest in meaning to CANDID.
- a. Secretive
- b. Frank
- c. Rude
- d. Clever
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Answer: B. Frank

Candid means open and honest in expression — frank. "Rude" is a trap: candid speech can be blunt, but the word itself carries honesty, not offensiveness.
Q17. Choose the word opposite in meaning to SCARCE.
- a. Rare
- b. Abundant
- c. Meagre
- d. Costly
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Answer: B. Abundant

Scarce means in short supply; its opposite is abundant (plentiful). "Rare" and "meagre" are near-synonyms of scarce placed as traps — in antonym questions, eliminate the synonyms first.
Q18. Fill in the blank: "Neither of the answers ___ correct."
- a. are
- b. is
- c. were
- d. have been
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Answer: B. is

"Neither" is grammatically singular, so it takes the singular verb "is" — the plural noun in "of the answers" does not change that. The same rule applies to "either", "each" and "every one".
Q19. Fill in the blank: "She has been working here ___ 2019."
- a. for
- b. since
- c. from
- d. till
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Answer: B. since

"Since" marks the starting point of a period (since 2019, since Monday); "for" measures its length (for five years). A year given as a starting point with a perfect-continuous tense always takes "since".
Q20. One word for "a person who can speak many languages":
- a. Polyglot
- b. Orator
- c. Bilingual
- d. Translator
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Answer: A. Polyglot

A polyglot speaks many languages (poly = many, glot = tongue). Bilingual is exactly two, an orator is a skilled public speaker, and a translator converts between languages professionally — knowing roots makes these one-word questions quick wins.
Q21. What is the value of x after this statement? int x = 7 % 3 + 4 * 2;
- a. 9
- b. 22
- c. 6
- d. 15
Show answer & explanation

Answer: A. 9

% and * bind tighter than +, so this is (7 % 3) + (4 × 2) = 1 + 8 = 9. Remember: in C-family languages %, * and / share the same precedence level, all above + and −.
Q22. How many times does the loop body run? for (i = 0; i < 10; i += 2)
- a. 4
- b. 5
- c. 6
- d. 10
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Answer: B. 5

i takes the values 0, 2, 4, 6, 8 — five iterations; at i = 10 the condition i < 10 fails. Counting formula: ⌈(stop − start) ÷ step⌉ = ⌈10/2⌉ = 5.
Q23. Which data structure processes elements in First-In-First-Out (FIFO) order?
- a. Stack
- b. Queue
- c. Binary tree
- d. Graph
Show answer & explanation

Answer: B. Queue

A queue serves elements in arrival order (FIFO), like a ticket line; a stack is the opposite (LIFO). Interviewers often follow up with real uses: printer job scheduling and BFS use queues, undo and recursion use stacks.
Q24. A function is defined as f(n) = f(n−1) + n with f(0) = 0. What is f(4)?
- a. 8
- b. 10
- c. 12
- d. 24
Show answer & explanation

Answer: B. 10

Unroll it: f(4) = f(3)+4 = f(2)+3+4 = f(1)+2+3+4 = f(0)+1+2+3+4 = 10 — the sum 1+2+3+4. Recognising a recurrence as a running sum (n(n+1)/2) saves time over tracing every call.
Q25. What is the worst-case time complexity of binary search on a sorted array of n elements?
- a. O(n)
- b. O(log n)
- c. O(n log n)
- d. O(1)
Show answer & explanation

Answer: B. O(log n)

Binary search halves the search space every step, so it needs at most ⌈log₂ n⌉ comparisons — O(log n). The prerequisite that trips people in interviews: the array must already be sorted, or the halving logic breaks.