How to become a Lightning Calculator by Anonymous is part of the HackerNoon Books Series. You can jump to any chapter in this book here. Proof of Multiplication in Ten Seconds.
Proof of Multiplication in Ten Seconds.
The unitate of a number is the sum of its digits reduced to a unit.
The unitate of the multiplier is 9 and the unitate of the multiplicand is 6; 6 times 9 equals 54, and the unitate of 54 is 9. Now the unitate of the product is found to be 9 also, which is a proof of the correctness of the work.
About HackerNoon Book Series: We bring you the most important technical, scientific, and insightful public domain books.
This book is part of the public domain. Anonymous (2021). How to become a lightning calculator. Urbana, Illinois: Project Gutenberg. Retrieved https://www.gutenberg.org/cache/epub/65078/pg65078-images.html
This eBook is for the use of anyone anywhere at no cost and with almost no restrictions whatsoever. You may copy it, give it away or re-use it under the terms of the Project Gutenberg License included with this eBook or online at www.gutenberg.org, located at https://www.gutenberg.org/policy/license.html.
[story continues]
tags