This book introduces methods for solving elementary school math problems in 5 seconds. - Title: 7 Secret Tools of Arithmetic - Author: Akito Ton - Publisher: Kanki Publishing - ISBN: 9784761231103 - Content: A book introducing methods for solving elementary school math problems in 5 seconds. - Price: 1100 yen + tax - 11th Edition, March 2025 Available for immediate purchase! It's new and unused, but has been stored at home, so please consider purchasing if you understand. Thank you.