This book is for young students Gifted or Advanced in math.
This book is about rational and irrational numbers. So the book covers non-integers real,
that is, rational and irrational numbers, and helps understand what those are about and
how they mingle with arithmetic operations so that you can not only use them properly
but can develop your own idea to make use of them, too, solving problems, of course.
It doesn’t just cover though, how to do arithmetic with rational or irrational umbers, that
is, it doesn’t merely explain how to apply to those numbers additions, subtractions,
multiplications, and divisions. But it helps also understand the nature of non-integers.
So this book covers the concepts of those numbers, and helps you understand them, and
use them efficiently as well as properly. And it can help speed up your calculation, too.
And some sample pages are at:
http://www.runmath.com/ExcerptFromArithmetic3SeongKim.pdf