As Peeik mentioned, the Year 11 and Year 12 Extension 1 Cambridge books have an excellent variety of questions and levels of difficulty.
I know the textbooks are titled "Year 11", "Year 12" and to make it worse, "Extension 1"! We must remember that these books also cover the Mathematics (2U Maths) course as well.
A very large number of topics in Year 10 actually appear in Year 11 and Year 12 as well.
For example:
- Trigonometry (all of it, including Sine Rule, Cosine Rule, Bearings, Trig Equations, Applications etc etc)
- Algebra (surds, indices and general algebra skills)
- Geometry (including circle geometry if the school decides to examine it).
- Compound/Simple interest and loans.
All of these topics are covered in great detail in the Cambridge series, so you may find them to be a great resource.
However, the Cambridge series does not cover 100% of the "Consumer Arithmetic" topic in Year 10. Things like 'Medicare Levy' and 'Tax Tables' are excluded, so you will of course need a proper Year 10 textbook to cover these. The best way to go is probably Mathscape 10, as Kazemagic said.