How to Solve CAT 2025 Quantitative Comparison Problems Easily

Quantitative Comparison (QC) questions in the CAT Quant section require logical reasoning and careful analysis rather than extensive calculations. In CAT 2024 Exam, QC questions accounted for approximately 10–12% of the Quant section, and many students lost marks due to over-calculation or incorrect assumptions. These questions present two quantities: Quantity A and Quantity B, and ask you to determine their relationship. This guide explains the QC format, effective strategies, and step-by-step examples to help you solve these questions efficiently and accurately.

What are Quantitative Comparison Problems?

Quantitative Comparison questions present two quantities, labeled Quantity A and Quantity B , along with conditions or constraints. Your task is to determine the relationship between them: whether one quantity is greater, both are equal, or the relationship cannot be determined. Exact numeric computation is often unnecessary; logical analysis and pattern recognition are more important.

Types of Answer Choices

• A: Quantity A is greater
• B: Quantity B is greater
• C: Both are equal
• D: Cannot be determined

QC questions appear across the Arithmetic, Algebra, and Number Systems topics. In the 2024 CAT exam, QC-style questions tested concepts such as ratios, percentages, inequalities, and simple algebra—areas that make up nearly 50–60% of the Quant section. Strengthening these fundamentals directly improves accuracy in QC problems.

Key Strategies to Solve QC Problems Easily

1. Simplify Before Comparing

• What to do: Factorize, cancel common terms, or rearrange expressions.
• Why it helps: Simplification often reveals the relationship directly, reducing calculation time.

2. Plug in Smart Values

• What to do: Substitute numbers for variables, including special cases: 0, 1, -1, ½, or very large values.
• Why it helps: Testing boundary cases helps confirm inequalities and relationships quickly.

3. Visualize or Approximate

• What to do: Use quick sketches, number lines, or mental diagrams.
• Why it helps: Estimation or visualization can identify the correct relationship without exact computation.

4. Eliminate Options Logically

• What to do: Rule out impossible choices based on a test case or logic.
• Why it helps: Even partial reasoning can narrow down options, increasing accuracy.

5. Manage Time Effectively

• What to do: Don’t linger on one question; mark and move on if needed.
• Why it helps: Focusing on solvable problems first ensures better overall performance in the Quant section.

Solved Examples: Step-by-Step QC Problem Breakdown

Example 1 – Plugging in Values Strategy

• Question: Compare Quantity A = x 2 −1 and Quantity B = (x−1)(x+1)
• Step 1 – Simplify / Test Values: Test simple numbers for xxx:
  • x=2 → Quantity A = 3, Quantity B = 3
  • x=−3 → Quantity A = 8, Quantity B = 8
• Step 2 – Analyze: Both expressions are identical mathematically.
• Answer: C (Both are equal)
• Takeaway: Plugging in smart values confirms equality without complex algebra.

Example 2 – Algebraic Simplification Strategy

• Question: Compare Quantity A = 1/n1/\sqrt{n}1/n and Quantity B = 1/n1/n1/n, for n>1n > 1n>1
• Step 1 – Simplify: Recognize that n<n\sqrt{n} < nn<n
• Step 2 – Infer: Then 1/n>1/n1/\sqrt{n} > 1/n1/n>1/n
• Answer: A (Quantity A is greater)
• Takeaway: Algebraic reasoning can often provide a direct comparison without plugging multiple numbers.

These examples are to help you review how you do not need to solve each question like a standard problem. but a quick logic is enough.

Expert Tips to Improve Accuracy and Speed in QC

To excel in QC questions, it’s essential to combine consistent practice with smart analysis. Regular exposure helps you recognize patterns and improves decision-making under time pressure.

• Daily Short Drills: Solve 2–3 QC questions every day for 10–15 minutes. Short, focused practice keeps your logic sharp.
• Learn from GRE-Style QC Sets: Different formats enhance adaptability and strengthen your approach to unseen question types.

Reviewing your problem-solving approach is just as important as getting the right answer. Observe where you spend most time, note common mistakes, and refine your strategies.

• Maintain a Mistake Log: Track repeated errors, such as sign mistakes or boundary case mishandling. Reviewing these regularly prevents repetition.
• Focus on Approach, Not Just Answers: Understand how each solution works, and practice arriving at it efficiently.

Finally, build intuition gradually and manage your time effectively. Spending too long on one problem can cost you marks elsewhere.

• Build Intuition Gradually: Prioritize understanding relationships between quantities over memorizing formulas.
• Time Management: Limit yourself to 2–3 minutes per QC question. Skip and return if unsure to maximize overall section performance.