Mental Maths Book for Class 9

The Mental Maths book for Class 9 by CREST Olympiads is written for the CREST Mental Maths Olympiad (CMMO) and can be bought as a colour PDF or a printed copy from the Olympiad books page.

The Class 9 CMMO syllabus the book is built on has seven topics:

1. Number System
2. Algebra
3. Comparing Quantities
4. Geometry
5. Mensuration
6. Playing with Numbers
7. Data Handling

What does the Class 9 book cover?

Class 9 drops the two Class 8 topics on squares and cubes and brings in more algebra and statistics. Within the seven topics, CREST's Class 9 study material covers simplification, polynomials and quadratic equations, factorisation, boats and streams, heights and distance, areas related to circles, number and alphanumeric series, statistics, probability and data interpretation. Classes 9 and 10 share one CREST Mental Maths workbook, in both the PDF and the printed format. It has a chapter of practice questions for each of the seven topics, then a CREST previous year paper and the answer key.

How does it help in the CMMO?

The Class 9 paper has 100 questions in 60 minutes. Many of them have a quick route once you see the structure, such as a difference of squares or a discount applied twice. Chapter-wise practice helps your child spot these patterns. A one-page sheet of formulas for interest, profit and loss, time and work and boats and streams, tested each morning, works well alongside the book.

To see the question style first, look at the free Class 9 Mental Maths sample papers. A boat covering 48 km downstream in 3 hours and a double discount of 30% and 20% are typical. The Class 9 Mental Maths reading material is free as well.