Εικόνες σελίδας
PDF
Ηλεκτρ. έκδοση
[merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][graphic][merged small][merged small]
[ocr errors]

COPYRIGHT, 1919

BY

HENRY HOLT AND COMPANY

PREFACE

This Second Book of Junior High School Mathematics continues the three lines of work, arithmetic, algebra, and geometry, begun in the First Book. In this, as in the First Book, the primary purpose is to teach the fundamental principles of arithmetic and to give skill in solving applied problems. The algebra is used to generalize the processes of arithmetic and as an aid in solving problems. The notions of geometry that have been presented furnish material for applied problems, the solutions of which use the arithmetic and the algebra.

The first chapters of this book give sufficient practice in the fundamental processes with algebraic symbols to prepare the pupil to use the formula, the equation, and the graph as tools for solving problems. It is believed that the use of algebraie symbols in the seventh and eighth grades, as provided for in these books, followed by a further study in the ninth grade, will give a mastery of algebra not possible in the present plan of giving all of the instruction in algebra in one year.

The processes of arithmetic, algebra, and geometry are unified in the study of ratio and proportion, similar figures, and the mensuration of surfaces and solids. The problem material here is taken largely from geometry. The explanations and methods of solution are simplified by the use of the equation and the algebraic notation.

The difficulties in the application of percentage and other parts of business arithmetic are mainly due to a lack of business experience and to a lack of knowledge of the facts with which the problems deal. Hence the more difficult parts of

462298

« ΠροηγούμενηΣυνέχεια »