A "Math in Air: Basics of numbers" is the first book in the series written as a learning and practicing guide in Mathematics. This book is intended for any student who wishes to learn and establish a strong foundation in basic math skills. Any student who is taking a pre-algebra course can use this book as a learning guide to enhance the understanding of various topics. This book covers topics including real number system, set theory, prime numbers, greatest common factor, fractions, radicals, percent and more. "The knowledge is only useful if you know when to use it and how to use it," the author says. Hence, the author puts greater emphasis on to practice examples throughout this book and encourages students to solve practice problems to master the skills.