It's better to work through the Foundations material in advance if you think you even
might need it. Too many of our students figure they can do without it, then realize halfway through the course that they aren't as prepared as they should be. If you are confident that you can factor down a quadratic equation, combine decimals, solve equations for two variables, etc., then you may not need Foundations of Math.
However, it is not enough simply to
understand the material. It's important that you can do these things automatically. I recommend that all students complete at least some of the Foundations drills. These can be great warmups at the beginning of a study session, or on the day of a test. The goal is to be able to perform simple manipulations quickly and easily, without a great deal of thought. This leaves your mind free to focus on the more complicated elements of a problem, and enables you to handle difficult material with more confidence and accuracy.
As to when to move on to the regular material, at the minimum you should feel good about chapters 4 & 5 before reading Number Properties. Chapters 1-3 and 8 apply specifically to Equations, Inequalities & VICs (our algebra book) and Word Translations, although it might help to read chapters 6 & 7 (fractions, decimals, and percents) as well, especially if you haven't worked with fractions for a while. Chapter 9 (geometry) can be saved until you are ready for the Geometry book.
If you are a non-native speaker, you may also wish to consider our Foundations of Verbal book.
I hope this helps. Good luck!
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