Legal notice
Responsible for this website
Pierre Christian Ulrich Singer, Entrepreneur individuel (EI)
Brand status
Singer Shamrock Enterprises — a brand of Pierre Christian Ulrich Singer, Entrepreneur individuel (EI). EST. 2026 is part of the branding.
Contact and service address
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+33 6 85 57 56 02
pcusinger@gmail.com
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This website is hosted through GitHub Pages by GitHub, Inc., 88 Colin P. Kelly Jr. Street, San Francisco, CA 94107, United States.
Privacy
This static version processes problems and answers entirely in the browser. It does not send training answers to a server and does not use analytics or advertising cookies.
The selected language may be stored locally in the browser. It remains on that device and can be removed by clearing browser data.
If user accounts, audience measurement, payment services, or external content are added later, this notice must be updated before those services are activated.
Terms of use
BRATS 11 is a learning and practice tool for strategic mental arithmetic. The displayed routes are intended to train mathematically equivalent transformations.
Although the site is checked carefully, uninterrupted availability and complete freedom from errors cannot be guaranteed. Do not base financial, legal, medical, or safety-critical decisions solely on this site's output.
The content, design, names, and training logic may not be reproduced or commercially distributed as another product without permission. Statutory private use and mandatory copyright exceptions remain unaffected.
Last updated: October 9, 2026