Proportions, rule of three, cross-multiplication, percentages - these are all calculations that can be confusing for many people. Fortunately, the Proportions - rule of three - percentages app, developed by Ledon, is here to help. This Android app is a simple, straightforward tool for calculating proportions and percentages.

With this app, you can easily calculate the most common cases of proportions, rule of three, cross-multiplication, and percentages. All you have to do is select incognito X and enter the data, and the app will do the rest. The user interface is clean and easy to navigate, so you won't have any trouble finding what you need.

Overall, Proportions - rule of three - percentages is a great app for anyone who needs to do calculations involving proportions and percentages. It's simple, easy to use, and does the job well. Best of all, it's free to download and use.