Arithmetic
TNPSC - Group 1 Paper 1 — Quantitative Aptitude
2-min read·10 key concepts·10 facts
AI-Powered Analysis
87
PYQs Analyzed
2019–2025
Years Covered
Paper 1
TNPSC - Group 1
This subtopic covers fundamental arithmetic operations, averages, percentages, ratios, and problem-solving techniques. It is crucial for TNPSC exams as it tests numerical ability and analytical skills.
Key Concepts
Average
Calculating mean value of numbers and its changes with addition/removal.
Percentages
Understanding and applying percentage calculations for savings, discounts, and growth.
Ratios and Proportions
Solving problems involving ratios, proportions, and their applications.
Simple and Compound Interest
Calculating interest, differences between S.I and C.I, and their formulas.
Work and Time
Determining time taken for tasks and work efficiency.
Number Theory
HCF, LCM, divisibility, and properties of numbers.
Algebraic Expressions
Simplifying and solving algebraic equations and fractions.
Geometry
Understanding properties of shapes, areas, and volumes.
Speed, Distance, Time
Calculating and applying formulas for speed, distance, and time.
Profit and Loss
Calculating profit, loss, and percentage changes in pricing.
Must-Know Facts
- 1Average formula: Sum of numbers / Count of numbers
- 2Percentage = (Part / Whole) × 100
- 3Ratio a:b = a/b
- 4Simple Interest = P × R × T / 100
- 5Compound Interest = P(1 + r/n)^(nt) - P
- 6Work = Time × Efficiency
- 7HCF is the highest common factor, LCM is the least common multiple
- 8Speed = Distance / Time
- 9Profit = Selling Price - Cost Price
- 10Loss = Cost Price - Selling Price
Exam Patterns
Most questions involve direct formula application
Percentage and ratio-based problems are frequent
Work and time problems often use efficiency ratios
Simple and compound interest questions test formula knowledge
Geometry problems require understanding of area/volume formulas
Common Traps
Confusing simple interest with compound interest
Miscalculating percentages due to decimal errors
Incorrectly applying ratio concepts in mixed problems
Forgetting to convert units in speed and time questions
Misapplying formulas for HCF and LCM
Year Highlights
2024High focus on percentage, ratio, and compound interest problems.
2025Increased emphasis on algebraic simplification and work-time problems.
Practice these PYQs
Test yourself with the actual 87 questions on Arithmetic