Rule of 3
Rule of 3 2.1 for Mac can be downloaded from our website for free. The actual developer of this Mac application is Everton Postay Cunha. You can run this app on Mac OS X 10.7 or later. The most popular versions among Rule of 3 for Mac users are 2.1 and 1.0. Our built-in antivirus scanned this Mac download and rated it as 100% safe. Rule of 3 for Mac lies within Productivity Tools, more precisely Calculators.
From the developer:
A simple App to help you calculating the rule of 3!
You may want to check out more Mac applications, such as Free Maps Ruler, Slide Rule or 2d ruler, which might be similar to Rule of 3.