ARITHMETIC BY JOHN B. GIFFORD AUTHOR OF "ELEMENTARY LESSONS IN PHYSICS "EVERYDAY BOSTON LITTLE, BROWN, AND COMPANY 1920 Edue T 119.20.430 HARVARD UNIVERSITY APR 24 1922 TRANSFERRED TO HARVARD COLLEGE LIDDAGY 1985 Copyright, 1920, BY LITTLE, BROWN, AND COMPANY. All rights reserved. PREFACE The object of this book is to make arithmetic a living, interesting subject, and to accomplish something worth while at the same time relieving the arithmetic hour from its general character of a daily grind by using as material the experience of everyday life. This familiar quality of the exercises contributes wonderfully to the interest, and this enhanced interest in the oral work results in a quickening of interest in the written work. To make this oral work most practical as a help to the regular textbook, this "New Mental Arithmetic" has been arranged on the topical plan. All the material in each division of the subject is placed together, naturally arranged, and carefully graded. (Most books on mental arithmetic are spiral rather than topical.) The pictures help out the text. They form an integral part of the method and contribute to the interest. The oral work, based on text and pictures, is indeed the arithmetic of everyday life. It enables pupils to do independent and rapid thinking. The use of the oral exercises in class enlivens teacher as well as pupil, forestalls and prevents dullness, and contributes to the success of the arithmetic work as a whole. III Multiplication by 10, 100, 1000, 5, 50, 500 By 15, 25, 75, 9, 99, 999, 98, etc. 66 67 V |