This book give all the concept clearly by which any student can understood any question better and this book also use or we say that most preffered for compitation examination. I suggest this book for railway, ssc, ips, is, etc. and many other examination .In this book the question are arranged in this way on every concept 4 or 5 question are solved and many other questions are unsolved for practice with their answer.I also use this book for compitation preparation.