1001 задача для умственного счета   By: Sergei Aleksandrovich Rachinskii (1836-1902)

"1001 задача для умственного счета" by Sergei Aleksandrovich Rachinskii is a fantastic resource for those looking to improve their mental math skills. The book is packed with a wide variety of challenging math problems that range in difficulty, allowing readers to gradually increase their proficiency in mental calculations.

I found the layout of the book to be particularly helpful, with each section focusing on a different type of math problem and providing clear explanations on how to solve them. The author's writing style is straightforward and easy to follow, making it accessible to readers of all levels.

Overall, I highly recommend "1001 задача для умственного счета" to anyone looking to sharpen their math skills and enhance their mental agility. Whether you are a student looking to improve your math grades or simply someone who enjoys a good mental challenge, this book is sure to keep you engaged and motivated.

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