RRB NTPC 2026 Maths: 20-Second Formulas & Type-Wise Questions

A mathematics book for the RRB NTPC computer-based tests that teaches the fastest method for each question type and then drills it — 343 questions, every answer worked out.

Mathematics carries 30 of the 100 questions in CBT-1 and 35 of the 120 in CBT-2, with 54 seconds a question in CBT-1 and a third of a mark lost for each wrong answer. The book opens with a time plan, the arithmetic of guessing, and the tables to know by heart.

Sixteen topic chapters follow the official syllabus: number system; LCM and HCF; simplification, powers, roots and decimals; ratio, proportion, partnership and mixtures; percentage; profit, loss and discount; simple and compound interest; averages and ages; time and work, pipes and cisterns; time, speed and distance with trains and boats; mensuration of plane figures and of solids; elementary algebra; geometry; trigonometry with heights and distances; and elementary statistics. Each gives the formulas and short cuts, worked examples and a practice set.

Three timed tests: two of 30 questions in the proportions of CBT-1 and one of 35 questions in the CBT-2 pattern. 82 pages.

Every question was written for this book; no question from any examination paper is printed here. Each computed answer was solved a second time, from the printed wording alone, by an independent program. This book is independent and is not published, approved or endorsed by the Railway Recruitment Boards or the Ministry of Railways.

Contents

• Getting Started
• How to Use This Book
• The Mathematics Section at a Glance
• The 54-Second Rule and Negative Marking
• Tables to Know by Heart
• Arithmetic
• 1. Number System
• 2. LCM and HCF
• 3. Simplification, Powers, Roots and Decimals
• 4. Ratio, Proportion, Partnership and Mixtures
• 5. Percentage
• 6. Profit, Loss and Discount
• 7. Simple and Compound Interest
• 8. Averages and Ages
• Work, Speed and Mensuration
• 9. Time and Work, Pipes and Cisterns
• 10. Time, Speed and Distance: Trains and Boats
• 11. Mensuration: Plane Figures
• 12. Mensuration: Solids
• Algebra, Geometry, Trigonometry and Statistics
• 13. Elementary Algebra
• 14. Geometry
• 15. Trigonometry, Heights and Distances
• 16. Elementary Statistics and Data
• Three Timed Maths Tests
• 17. Maths Test 1
• 18. Maths Test 2
• 19. Maths Test 3 (CBT-2 Pattern)