Important Chapters for Class 10 Maths CBSE — Weightage and Tips

CBSE Class 10 Maths Chapter Weightage Overview

The CBSE Class 10 Mathematics paper is 80 marks (20 marks for internal assessment). The 2026 term structure covers all 15 chapters across Number Systems, Algebra, Coordinate Geometry, Geometry, Trigonometry, Mensuration, and Statistics/Probability.

High-weightage units (12–13 marks each): Algebra (Polynomials, Pair of Linear Equations, Quadratic Equations, Arithmetic Progressions), Geometry (Triangles, Circles, Constructions). These two units together account for approximately 30–35 marks.

Medium-weightage units (10–12 marks): Trigonometry (Introduction to Trigonometry, Applications) — 12 marks; Mensuration (Areas, Surface Areas and Volumes) — 10 marks; Statistics and Probability — 11 marks.

Lower-weightage but scoring units: Number Systems (Real Numbers) — 6 marks; Coordinate Geometry — 6 marks. These are relatively easy to score full marks in with focused preparation.

Algebra — The Highest Weightage Unit

Algebra carries the most marks in Class 10 Maths and must be thoroughly prepared. It covers four chapters:

Polynomials: Understand the relationship between zeroes and coefficients of quadratic polynomials (sum = -b/a, product = c/a). Questions typically ask you to find zeroes, verify relationships, or find a polynomial given its zeroes. 2–3 marks questions from this chapter.

Pair of Linear Equations in Two Variables: Methods — graphical, substitution, elimination, cross-multiplication. Word problems (age, coins, work, mixture) are very common in 3-mark and 5-mark questions. Practice 20–25 word problems from previous year papers.

Quadratic Equations: Solving by factorisation and quadratic formula, discriminant (nature of roots). Word problems converting real-world scenarios to quadratic form are the highest-mark questions (5 marks) from this chapter. The discriminant test (D = b²-4ac) determines whether roots are real, equal, or imaginary.

Arithmetic Progressions: nth term formula (aₙ = a + (n-1)d), sum of n terms (Sₙ = n/2[2a + (n-1)d]), finding missing terms. Very formula-driven — learn all standard results and practise applying them under time pressure.

Geometry — Triangles and Circles

Geometry is the second most important unit. Two chapters dominate:

Triangles: This is the single most important chapter in Class 10 Maths. The Basic Proportionality Theorem (Thales' theorem) and its converse appear almost every year — usually a 3-mark or 5-mark proof question. AAA, SSS, SAS similarity criteria must be memorised. Area of similar triangles theorem (ratio of areas = square of ratio of corresponding sides) is another exam favourite. Practice proving theorems, not just applying them — CBSE requires step-by-step geometric proofs with reasons.

Circles: Tangent to a circle, properties of tangents (tangent perpendicular to radius, tangents from external point are equal in length). The two theorems — tangent is perpendicular to radius, and two tangents from external point are equal — appear regularly in 2–3 mark questions. Constructions (tangent from external point, triangle similar to given triangle) are tested as 3-mark questions.

Trigonometry, Mensuration, and Statistics

Trigonometry (12 marks): Introduction to Trigonometry chapter requires memorising trigonometric ratios (sin, cos, tan, cosec, sec, cot), standard angle values (0°, 30°, 45°, 60°, 90°), and 8 fundamental identities. Prove-the-identity questions (3 marks) and evaluate-expression questions (1–2 marks) are most common. Some Applications of Trigonometry — heights and distances using angle of elevation and depression — appears as 3–5 mark word problems. These are very formula-dependent but straightforward once you understand which sides are opposite, adjacent, and hypotenuse relative to the angle.

Mensuration (10 marks): Surface Areas and Volumes of combinations of solids (cone + cylinder, sphere + cylinder, frustum). Frustum of a cone formulas appear almost every year as a 3-mark question. Volume and surface area problems require knowing all 6 formulas for cube, cuboid, cone, cylinder, sphere, and hemisphere.

Statistics and Probability (11 marks): Mean (direct, assumed mean, step-deviation methods), median (cumulative frequency, formula), mode (modal class formula). Cumulative frequency curve (ogive) drawing and reading median graphically is a 3-mark question that appears annually. Probability — theoretical probability of events, particularly for playing cards, dice, and balls-in-bag scenarios — is usually 2–3 straightforward questions.

Real Numbers and Coordinate Geometry — Easy Full Marks

Real Numbers (6 marks): Only two main topics — Euclid's Division Lemma and Fundamental Theorem of Arithmetic. Euclid's algorithm to find HCF (step-by-step division) is a 3-mark standard question. Proving irrationality of surds (√2, √3, √5, etc.) by contradiction method appears as 3-mark proof questions almost every year. This chapter is very formula-light — it rewards careful logical writing. Full marks in Real Numbers is very achievable with 2–3 hours of focused practice.

Coordinate Geometry (6 marks): Section formula (internal division), midpoint formula, distance formula, and area of triangle formula are the four tools this chapter uses. Questions are computation-based — given coordinates, find distance, midpoint, section ratio, or area. No concept gaps here — it is entirely formula application. Practice 15–20 numerical questions from each formula to build speed and accuracy. These 6 marks are among the easiest to secure in the entire paper.