Infosys Logical Reasoning 2026: Questions and Strategies

Infosys logical reasoning tests five topic types beyond number series: syllogisms, blood relations, coding-decoding, statement-conclusion, and data sufficiency.

The Infosys number series guide covers the six quantitative pattern types in the aptitude test: arithmetic, geometric, square/cube, prime, Fibonacci, and alternating series. This article covers the five logical reasoning categories that fall outside that quantitative section. Each has a mechanical approach that works reliably under timed conditions.

What the Infosys Reasoning Ability Section Tests

The Infosys online aptitude test gates all three hiring tracks. Clearing it is the entry condition for any of the compensation bands below.

Track	Starting CTC	Key requirement
System Engineer (SE)	₹3.6 LPA	Standard aptitude plus technical interview
Specialist Programmer (SP)	₹6.5 LPA	Stronger DSA coding section; InfyTQ certification holders preferred
Power Programmer (PP)	₹9.5 LPA	HackWithInfy top performers; 7.5+ CGPA; InfyTQ required

The reasoning ability section sits alongside the quantitative and verbal sections in the same timed test. For the full picture of what the Infosys aptitude test covers, including test structure and time allocation across all sections, that is the right starting point.

This article focuses on the five reasoning categories. Number series, which belongs to the quantitative block, is out of scope here. Each reasoning category below is covered with at least two solved examples and a mechanical strategy.

Syllogisms: Two Statements, Venn Diagram Logic

Syllogism questions give two or three statements and ask which conclusions necessarily follow. The approach: draw mental Venn diagrams. Only what the diagrams force is valid. Real-world knowledge does not help and often misleads.

Three diagram rules cover the majority of questions:

• “All A are B” means A’s circle sits fully inside B’s circle.
• “Some A are B” means the circles overlap partially.
• “No A are B” means the circles share no overlap at all.

Practice Questions

• Q1. Statements: (1) All cats are animals. (2) All animals are living things. Conclusions: (I) All cats are living things. (II) Some living things are cats.

• Analysis: All cats sit inside animals; all animals sit inside living things; so all cats sit inside living things. Conclusion I follows directly. Since cats exist and are living things, some living things are cats. Conclusion II also follows.

• Answer: Both conclusions follow.

• Q2. Statements: (1) Some doctors are engineers. (2) All engineers are scientists. Conclusions: (I) Some doctors are scientists. (II) All scientists are doctors.

• Analysis: The doctors who are engineers are also scientists, so some doctors are scientists. Conclusion I follows. Nothing in the statements forces all scientists to be doctors. Conclusion II does not follow.

• Answer: Only Conclusion I follows.

• Q3. Statements: (1) No book is a pen. (2) Some pens are erasers. Conclusions: (I) No book is an eraser. (II) Some erasers are not books.

• Analysis: Books and pens share no overlap. Some pens are erasers. We have no direct information about the relationship between books and erasers, so Conclusion I (no book is an eraser) is too strong to assert. By symmetry from Statement 1, no pen is a book. Since some pens are erasers, those pen-erasers are not books. Therefore some erasers are not books. Conclusion II follows.

• Answer: Only Conclusion II follows.

Blood Relations: Draw First, Then Decode

Blood relation questions chain two to five relationship statements. Trying to hold the full chain in your head is the most common mistake. Draw a simple tree with arrows as you read each statement, then read the answer off the diagram.

Shorthand: arrows point from parent to child. Label gender when stated.

Practice Questions

• Q1. Pointing to a photograph, Anil says, “She is the daughter of my grandfather’s only son.” How is the woman related to Anil?

• Step 1: Grandfather’s only son = Anil’s father.

• Step 2: Daughter of Anil’s father = Anil’s sister.

• Answer: Sister.

• Q2. A is B’s brother. C is A’s mother. D is C’s father. How is A related to D?

• Step 1: D is C’s father and C is A’s mother, so D is A’s maternal grandfather.

• Step 2: A is male (established from “A is B’s brother”), so A is D’s grandson.

• Answer: Grandson.

Coding-Decoding: Identify the Rule from the Sample

Every coding-decoding question carries its own rule inside the sample pair. Check the first two or three letters of the encoded sample to confirm the rule. Do not assume a +1 shift until you have verified it. Apply the confirmed rule to the target word.

Practice Questions

• Q1. If PENCIL is coded as RGPEKN, what is the code for ERASER?

• Rule identification: P(16) to R(18) is +2; E(5) to G(7) is +2; N(14) to P(16) is +2. Each letter shifts forward by 2 positions.

• Apply to ERASER: E(5) to G(7), R(18) to T(20), A(1) to C(3), S(19) to U(21), E(5) to G(7), R(18) to T(20).

• Answer: GTCUGT.

• Q2. In a code, APPLE is written as BQQMF. What is the code for MANGO?

• Rule identification: A(1) to B(2) is +1; P(16) to Q(17) is +1; L(12) to M(13) is +1. Each letter shifts forward by 1 position.

• Apply to MANGO: M(13) to N(14), A(1) to B(2), N(14) to O(15), G(7) to H(8), O(15) to P(16).

• Answer: NBOHP.

Statement-Conclusion: Strict Logic, Not Common Sense

Statement-conclusion questions test whether a conclusion follows directly and necessarily from the given statement. Common knowledge or reasonable inference does not qualify. If the conclusion requires any information not present in the statement, it does not follow.

A useful check: apply the contrapositive. If “All A are B” is the statement and “Ravi is not B” is a given, then “Ravi is not A” follows by contrapositive.

Practice Questions

• Q1. Statement: Regular exercise leads to good health. Priya exercises every day. Conclusions: (I) Priya has good health. (II) Priya never falls sick.

• Analysis: Combining both premises: regular exercise leads to good health, and Priya exercises every day, so Priya has good health. Conclusion I follows directly. Conclusion II extends beyond the statement. Good health does not mean never falling sick; the statement makes no such claim.

• Answer: Only Conclusion I follows.

• Q2. Statement: All hardworking students get good grades. Ravi did not get good grades. Conclusions: (I) Ravi is not a hardworking student. (II) Ravi is lazy.

• Analysis: By contrapositive: if not good grades, then not hardworking. Conclusion I follows. Conclusion II labels Ravi lazy, but “not hardworking” and “lazy” are not equivalent. The statement does not support Conclusion II.

• Answer: Only Conclusion I follows.

Data Sufficiency: Is It Solvable, Not What Is the Answer

Data sufficiency questions ask whether the given statements provide enough information to answer a question. You do not need to compute the answer. You only need to determine whether computing it would be possible.

Resist the impulse to solve. Ask once: “If I had to use only Statement 1, could I?” Then ask the same for Statement 2. That is the entire task.

Standard answer codes in the Infosys test format:

• (A) Statement 1 alone is sufficient.
• (B) Statement 2 alone is sufficient.
• (C) Both statements together are sufficient, but neither alone is.
• (D) Neither statement alone nor together is sufficient.

Practice Questions

• Q1. Is n divisible by 6?

  • Statement 1: n is divisible by 3.
  • Statement 2: n is divisible by 2.

• Analysis: Statement 1 alone: n could be 3, 9, or 15; none of these are divisible by 6. Insufficient. Statement 2 alone: n could be 2, 4, or 10; none of these are divisible by 6. Insufficient. Both together: a number divisible by both 2 and 3 is divisible by 6, since 2 and 3 share no common factor. Sufficient.

• Answer: (C) Both statements together.

• Q2. What is the value of x + y?

  • Statement 1: x minus y equals 4.
  • Statement 2: x plus 3y equals 20.

• Analysis: Statement 1 alone: one equation, two unknowns. Insufficient. Statement 2 alone: one equation, two unknowns. Insufficient. Both together: subtract Statement 1 from Statement 2 to get 4y = 16, so y = 4 and x = 8, giving x + y = 12. Sufficient.

• Answer: (C) Both statements together.

Time Allocation for the Reasoning Section

The Infosys online test runs under real time pressure. These per-topic methods reduce average time per question.

• Syllogisms: Draw the Venn circles before reading the conclusions. Two minutes of setup prevents five minutes of second-guessing.
• Blood relations: One arrow-diagram on scrap paper, updated with each new relationship statement. Holding more than two steps in your head at once causes chain-reading errors.
• Coding-decoding: Decode only the first three letters of the sample word to confirm the rule. That is enough. Do not verify the full sample word before applying the rule to the target.
• Statement-conclusion: Re-read the statement text, not your general knowledge. A conclusion is valid only if it cannot be false given the statement as written.
• Data sufficiency: Evaluate each statement independently before combining them. Never evaluate both simultaneously on the first pass.

For a broader view of how the logical reasoning section fits alongside the quantitative and verbal blocks, the Infosys aptitude test guide covers overall test structure and section-level time budgets.

Infosys Hiring in 2026

Infosys onboarded 20,000 freshers in FY26 and plans to reach the same number in FY27, per CEO Salil Parekh’s Q4 FY26 earnings commentary. At that hiring volume, the aptitude test functions as a genuine first-round filter rather than a formality.

Parekh also stated in the same commentary that Infosys now offers different starting compensation for candidates with AI-attuned skills and is building a “forward-deployed engineer” pool to work directly with clients on AI solutions. The InfyTQ certification from Infosys signals the kind of technical preparation the SP and PP tracks look for.

Knowing when you have enough information to act is the point of data sufficiency questions. The same logic applies to placement readiness: clearing the reasoning section is a necessary condition, not a sufficient one. TinkerLLM (₹299) covers LLM fundamentals (API calls, prompt structure, and RAG basics) in a self-paced format.