This book helps your child easily master all the addition and subtraction of three numbers. Addition and Subtraction Workbook of 100 pages and more - an excellent tool - for building confidence in arithmetic skills. - over 6 years old - Record score and time to see improvements - Includes answer pages - Consistent practice leads to results. It contains 100 exercises and a total of 1200 operations with answers that will help your child easily add and subtract.