Comenius Abbatiale Saint Etienne Dipl.-Math. T. Günther

At the 2012 Comenius meeting in France we visited the Abbatiale Saint Etienne.

Three stones of its wall are arranged in a (part of an) circle:

1. Exercise: The arclength b1 and b2 and the distance d of the two circles can be meassured: b1 = 60cm, b2 = 70cm andd = 25cm (see sketch above). Determine the radius r of the smal circle.

2. Exercise: Establish a formula for the radius r in general case.

1