Defence | NDA & NA
NDA & NA sets 120 Mathematics questions for 300 marks in the Written Examination — Paper I: Mathematics, so it is worth planning your preparation around the topics below.
The quantitative core of the railway papers: arithmetic, mensuration, and time-speed-distance built on a secondary-school foundation. Fluency with fractions, percentages and ratios underlies almost every question, so that is where practice pays back fastest.
How much Mathematics is worth in each NDA & NA stage, from the official pattern.
| Stage | Questions | Marks | Time | Share |
|---|---|---|---|---|
| Written Examination — Paper I: Mathematics | 120 | 300 | — | 100% |
Every topic in the official syllabus. The linked ones open a set of solved questions you can practise straight away.
Written to the NDA & NA pattern, with the answer key and the method behind it — a look at how the section is actually set before you drill the full topic sets.
Quadratic equations · solved example
In each, solve for x and y and give the relation: I. x² − 17x + 66 = 0 II. y² + 5y − 66 = 0
Solution
The roots are x = 6, 11 and y = -11, 6. Comparing every x with every y gives "x ≥ y".
Data interpretation · solved example
From the table, what is the total number of units sold across all four products?
Solution
Adding the four figures: 180 + 140 + 180 + 80 = 580.
Mensuration · solved example
The area of a circle is 154 cm². Find its radius (take π = 22/7).
Solution
πr² = 154, so r² = 154 × 7/22 = 49 and r = 7 cm.
Mixtures and alligation · solved example
A 60-litre mixture has milk and water in the ratio 2 : 1. How much water must be added to make the ratio 1 : 1?
Solution
The mixture has 40 litres milk and 20 litres water. To match the 40 litres of milk, water must reach 40 litres, so 40 − 20 = 20 litres are added.
Advertisement
Mathematics shows up in every NDA & NA mock test, in the same interface, with sectional locking and negative marking.
NDA & NA: 9-question practice mock
9 questions | 10 min
NDA & NA NDA & NA (II) 2026 — NDA 158th Course sets 120 Mathematics questions for 300 marks in the Written Examination — Paper I: Mathematics.
Yes. NDA & NA deducts one third of a mark for each wrong answer, Mathematics included, so unsure guesses cost you. Each correct answer earns 2.5 marks and one third of that (0.83 marks) is deducted for each wrong answer. Unanswered questions carry no penalty.
The NDA & NA syllabus lists Algebra: sets, complex numbers, quadratic equations, sequences and series, Matrices and determinants, Trigonometry and inverse trigonometric functions, Analytical geometry of two and three dimensions, Differential and integral calculus, and differential equations, Vector algebra and more. Weight your revision towards the ones you are weakest on and confirm the emphasis against the paper analysis for recent cycles.
Every Mathematics question on this site is free and written to the exam pattern. Use the topic drills for instant-feedback practice, the daily quiz to keep the section warm, and the NDA & NA mock tests to sit it under a real clock with negative marking.