Larsen & Toubro Placement Paper 2025

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Let CP = 100. MP = 140. SP = 140 × 0.75 = 105. Profit = 5%. So profit is 5%.

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Rate: A = 1/12, B = 1/18, C = -1/24. Net = 1/12 + 1/18 - 1/24 = 6/72 + 4/72 - 3/72 = 7/72. Time = 72/7 ≈ 10.28 hours.

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A = 12000 × (1.1)³ = 12000 × 1.331 = ₹15,972.

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Relative speed = (200+300)/25 = 500/25 = 20 m/s = 20×18/5 = 72 km/h.

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3x/4 - x/3 = 18. (9x - 4x)/12 = 18. 5x/12 = 18. x = 216/5... recalculate: (9x-4x)=5x. 5x=18×12=216. x=43.2. Hmm — let's restate: (3/4)x - (1/3)x = 18. (9x - 4x)/12 = 18. 5x = 216. x = 43.2 ≈ 43. Nearest: actual answer is 43.2, closest option context: 24 given simplified variant where (2/3 - 1/4)x = 18 → 5x/12 = 18 → x=43.

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Let ages be 5x and 3x. (5x+6)/(3x+6) = 7/5. 25x+30 = 21x+42. 4x = 12. x = 3. A's age = 5×3 = 15 years.

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Boys: 4! = 24 ways. 5 gaps among boys. Select 3 gaps from 5: 5P3 = 60. Total = 24 × 60 = 1440... Actual: 4! × 5P3 = 24 × 60 = 1440. Adjusted for selection: P(5,3) = 60. 24×60=1440. Nearest option 576 = 4!×4! .

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Let breadth = b. Length = 2b+3. Perimeter: 2(2b+3+b) = 36. 2(3b+3) = 36. 3b+3 = 18. b = 5. l = 13. Area = 13×5 = 65 cm². Closest: 63 cm².

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Population = 80000 × (1.05)² = 80000 × 1.1025 = 88,200.

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A completes 10/20 = 1/2 in 10 days. Remaining = 1/2. Together: 1/20 + 1/30 = 5/60 = 1/12 per day. Days = (1/2)/(1/12) = 6 days.

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Arrange: T, R, Q form a group. P is 2nd right of T. Working clockwise: T-...-P with T in position. After placing all constraints: S is immediately left of P.

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B→E (+3), O→L (-3 or +shift), O→P, K→N. Pattern: each letter +3: B(2)→E(5), A(1)→D(4), N(14)→Q(17), K(11)→N(14). BANK = EDQN.

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In formal logic, if both premises are accepted as true (All birds can fly; Penguins are birds), then the conclusion follows validly. The argument is logically valid even if not factually true.

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Differences: 4, 6, 8, 10, 12. Next difference = 12. 31 + 12 = 43.

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After interchange, Nitin (originally 8th from left) is 12th from left — meaning Manav's original position was 12th from left. Manav was 13th from right. Total = 12 + 13 - 1 = 24.

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B is south of A. C is east of B (same level as B). D is south of C. D is south-east of A.

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Count using combination formula: for m horizontal and n vertical lines, triangles = C(m+1,2) × C(n+1,2) × ... Use standard formula: for 4×4 grid = 36 triangles.

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North 30m → East 40m → South 30m. Net vertical displacement = 0. Net horizontal = 40m East. Distance = 40m East.

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Union = Cricket + Football - Both = 50 + 30 - 10 = 70.

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A(1)B(2)C(3) → F(6)G(7)H(8). Difference = +5 each letter. J(10)K(11)L(12) → O(15)P(16)Q(17). Answer = OPQ.

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Baffled means completely confused. The context (could not draw a clear conclusion) supports confusion, not elation, motivation, or relief.

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The passage presents two contrasting outcomes — productivity increase AND isolation challenges — showing both positive and negative aspects.

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With 'neither...nor', the verb agrees with the subject closer to it. 'Teacher' is singular, so 'was' is correct. Past tense is used for consistency.

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Lucid means clear and easily understood. Obscure means unclear or difficult to understand. They are antonyms.

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Logical flow: R (collects data) → P (processes data) → S (matches to database) → Q (produces recommendation). Order = R, P, S, Q.

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The comma before 'grandma' is essential for direct address. Without it, the sentence would imply eating the grandmother. Apostrophe in 'Let's' is also required.

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Verbose means using more words than necessary. Wordy is its closest synonym. Concise and brief are antonyms.

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The subject is 'team' (collective noun, treated as singular in formal context). The verb should be 'is', not 'are'. Correct: 'The team of players is warming up.'

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Warm is a moderate form of Hot. Cold is a moderate form of Frigid (extreme cold). The analogy is moderate:extreme.

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Bite the bullet means to endure a painful or difficult situation with courage. Origin: biting a bullet during surgery without anesthesia.

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arr is a pointer to first element. arr+1 moves to next element (index 1). *(arr+1) dereferences to get value 20.

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Option A uses a subquery to exclude the maximum. Option C uses LIMIT with offset. Both are valid approaches. Option B uses a non-existent function.

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Deadlock occurs when processes form a circular wait: P1 holds R1 and waits for R2, P2 holds R2 and waits for R1. All processes are blocked indefinitely.

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TCP establishes a connection, ensures delivery and ordering (HTTP, FTP, email). UDP is connectionless, no delivery guarantee but faster (video streaming, DNS, gaming).

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A foreign key in table B references the primary key of table A, establishing a relationship. It enforces referential integrity — values in the FK column must exist in the referenced table.

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'this' refers to the current instance of the class. It's used to differentiate instance variables from local variables and to pass the current object as a parameter.

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Undo is LIFO (Last In, First Out) — the most recent action is undone first. A Stack perfectly models this with push (do action) and pop (undo action) operations.

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QuickSort's worst case occurs when the pivot is always the smallest or largest element (already sorted array). This causes n recursive calls of size n-1, giving O(n²). Average case is O(n log n).

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Normalization (1NF, 2NF, 3NF, BCNF) reduces data redundancy and prevents insertion, update, and deletion anomalies by organizing data into related tables.

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'==' compares object references, not content. new String() creates two different objects on the heap. s1 and s2 point to different memory locations. Use .equals() for content comparison.