The "Mental Arithmetic Book 4" is a paperback book authored by Schofield and Sims, focusing on exam preparation in the subject of Mathematics. This book, published by Schofield & Sims LTD, is written in English and targets students looking to improve their arithmetic skills. The content is structured to help students prepare for exams by providing practice problems and guidance on mental arithmetic techniques. It is a valuable resource for students looking to enhance their mathematical abilities and perform well in exams.