Each test fiber was produced 5 times under similar conditions and its strength was tested on 5\ identical devices. Assuming that each fiber has the same strength, the number of breaks of a given fiber should\ be binomially distributed with five trials and an unknown probability p of fiber break. If all fibers are of the\ same strength, p should be the same for all of them, if they are of different strength, p should vary from fiber to\ fiber. The following table summarizes the outcome of the experiment: