Ratio and Proportion, Concepts, Short Tricks, and Strategies

Ratio and Proportion is an important topic in quantitative aptitude. Questions from this topic are less time-consuming and easy to solve. In this blog, we have provided the key formulas to solve ratio and proportion questions, along with short tricks and strategies.

What Is Ratio and Proportion in Quantitative Aptitude?

Ratio is a comparison of two quantities using division. It shows how many times one quantity is contained in another.

Proportion states that two ratios are equal. It is a statement showing equivalence of two ratios.

This topic appears in exams because it tests basic arithmetic reasoning, logical comparison, and problem-solving speed, especially in financial and commercial scenarios.

Skills required:

  • Logical comparison
  • Fast simplification
  • Applying inverse/compound ratio techniques

Why Is Ratio and Proportion Important in Competitive Exams?

One to two questions always come from this topic, which are easy to solve and less time-consuming. The details of the number of questions asked from this topic are as follows:

ExamNo. of QuestionsDifficulty
SSC CGL / CHSL1–2Easy
IBPS PO / SBI PO1–2Moderate
RRB NTPC / Group D1Easy
State PSC / Police1–2Moderate

Terms Used in Ratio and Proportion Questions

The terms that are commonly used to solve questions based on ratio and proportion are as follows:

TermExplanation
Ratio (a : b)Comparison between two quantities (a is to b)
Proportion (a : b = c : d)Two ratios are said to be in proportion; a/b = c/d
Cross MultiplicationIf a/b = c/d, then a × d = b × c
Continued ProportionIf a : b = b : c, then b is the mean proportional
Mean ProportionMean of two numbers a and b is √(ab)
Third ProportionIf a : b = b : c, then c is the third proportion
Duplicate RatioThe ratio of squares: a² : b²
Inverse RatioWhen the product of elements is constant; reverse relationship
Compound RatioResultant of multiplying two or more ratios: ac : bd
Equivalent RatiosRatios that represent the same relationship, e.g., 2:4 = 1:2

What Are the Types of Ratio and Proportion Questions in Quantitative Aptitude?

Types of questions that are asked in ratio and proportion are as follows:

  • Direct Ratio Problems: Straightforward comparison
  • Proportion-based Word Problems: “If A : B = 2:3 and B : C = 4:5, find A : C”
  • Mixture & Partnership Problems: Based on proportional shares
  • Time-Work/Money Ratios: Embedded in compound problem statements
  • Inverse Ratio: Scenarios involving speed-time or men-work questions

Ratio and Proportion Formulas for Quantitative Aptitude

Formulas used to solve ratio and proportion questions are as follows:

Rato and Proportion formulas

Ratio and Proportion Tricks for SSC CGL and Other Exams

Tricks to solve ratio and proportion quantitative aptitude questions are as follows:

  1. Convert all ratios into fractions for faster simplification
  2. Use cross-multiplication to verify proportionality
  3. Combine ratios step-by-step for chain ratio problems
  4. Remember standard triples: 2:3:4, 3:4:5
  5. In partnership/money questions, treat ratio as share units
  6. For reverse calculations, use inverse ratio directly

Solved Ratio and Proportion Questions from 2024–25 Exams

Question 1:

Asked in SSC CGL 2024 Tier 1 Shift 2 – Memory-Based
If A : B = 3:5 and B : C = 2:7, find A : B : C.

Answer:
A : B = 3:5
B : C = 2:7
Make B common: LCM of 5 and 2 = 10
A:B = 6:10, B:C = 10:35 → A:B:C = 6:10:35

Question 2:

From IBPS PO Prelims 2024 – Memory Based
A sum of ₹8400 is divided between A and B in the ratio 5:2. What is B’s share?

Answer:
Total parts = 5 + 2 = 7
B’s share = 27×8400=₹2400\frac{2}{7} \times 8400 = ₹240072​×8400=₹2400

Question 3:

Asked in RRB NTPC 2024 – Memory-Based
If a:b = 4:5 and b:c = 6:7, find a:c.

Answer:
a:b = 4:5, b:c = 6:7
Make b common (LCM of 5 and 6 = 30)
a:b = 24:30, b:c = 30:35 → a:c = 24:35

Ratio and Proportion Concepts for Bank Exams

Bank exams often include compound ratios, time-work based proportions, or profit-loss proportions.

Example:
A and B invest in a business in the ratio 5:4. After 8 months, C joins and the profit is divided in the ratio 20:16:9. Find for how many months C invested.

→ Use ratio × time = share for each partner and solve proportionally.

Common Mistakes to Avoid while Solving Ratio and Proportion

While solving Ratio and Proportion Quantitative Aptitude questions, candidates must keep the below points in mind:

  1. Confusing proportion with percentage comparison
  2. Not equalizing common terms before combining ratios
  3. Dividing incorrectly while distributing quantities
  4. Skipping units (Rs, kg, hrs) in word problems
  5. Failing to reduce ratios to their simplest form before solving

What Are Related Topics I Should Revise Next?

Topics you should revise next are as follows:

  • Questions based on Time and Distance
  • Rules and Practice Questions of Simplification
  • Shortcuts and Patterns of Number Series
  • Various types of Questions Based on Data Interpretation
  • Tricks & Examples of Inequalities

FAQs

Q1. What is the basic concept of ratio and proportion?

A ratio compares two quantities, while proportion states that two ratios are equal.

Q2. How do I find the third proportion between two numbers?

If a : b = b : c, then c is the third proportion, calculated as c = b² / a.

Q3. How do I simplify compound ratio problems quickly?

Multiply corresponding terms directly: (a : b) × (c : d) = ac : bd.

Q4. Is it necessary to reduce ratios to the lowest terms?

Yes, simplifying helps avoid calculation mistakes and makes comparisons easier.

Q5. What are common mistakes in solving proportion questions?

Mixing up terms, incorrect cross multiplication, and wrong unit assumptions.


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