3. Estimation
6. Integers
7. Fractions
9. Decimals
11. Unitary Method
12. Percentage
13. Profit and Loss
14. Simple Interest
15. Exponents
18. Mensuration
19. Geometry
19.1. Lines and Angles
19.2. Triangles
19.2.3. Properties of a Triangle
19.2.3.1. Angle Sum Property of a Triangle
19.2.3.2. Exterior Angle Property of a Triangle
19.2.3.3. Triangle Inequality
19.2.3.4. Pythagoras' Theorem
19.3. Congruence
22. Probability
23. Data Handling