This utility app helps you solve problems involving ratios and proportions. It calculates an unknown number based on the relationship between two other known numbers.
Rule of Three Calculator by Saran Dumronggittigule


16+ similar apps compared and reviewed
Whether you want more options like ArduinoBlue or a completely different take on the same concept, our curated list of 16+ similar apps has you covered. Updated for 2026 with the latest ratings and comparisons.


This utility app helps you solve problems involving ratios and proportions. It calculates an unknown number based on the relationship between two other known numbers.



This app provides comprehensive mobile services for campus cards, including traditional card functions like consumption and authentication, enhanced with QR code capabilities. It offers features for managing your campus card, paying various campus fees, and booking campus facilities.






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