First, download the Linux version of RealPlayer from here.
Once the .bin file has been downloaded to your desktop, right-click on it and select Properties. Then select the Permissions tab, tick “Allow executing file as program” and click Close.
After that, open Terminal (Applications -> Accessories -> Terminal), type the following commands and press Enter. (Remember to change the text in red according to the name of the file you downloaded.)
The installation will now begin.
You will be asked to enter the directory where you want to install RealPlayer. To install in the default directory, press Enter.
Next you will be asked whether you want to proceed or go to the previous step. Press Enter to proceed. After a few seconds the installation wil be completed. Close the Terminal window.
Alternatively you can download the .deb package from the site and double-click on it to start the installation. This would be the easier method.
You can open RealPlayer by going to Applications -> Sounds & Video.