http://img15.hostingpics.net/pics/801346Sanstitre2.png Picture of final result.

Ferenc came with the following "uncertain" result: 175/225-250
KGM came with the following result: 225-275
As for me, I first thought it was 225-250 but I completely forgot to check out my ball at right. It happens, after using the circle methods and zoom in on Paint and Photofiltre that it is indeed 50 pts for me and not 25.

You can make sure by yourself using the picture above.

So 225-275 appears to be the definitive result. You can always discuss it here.