Question 13
Isosceles triangle $ABC$ has been dissected into thirteen isosceles acute triangles, as shown in the two following diagrams, where all segments of the same length are marked the same way, and the second diagram shows the details of the dissection of triangle $EFG$. Given that $\angle CAB$ has an integral value, in degrees, what is the measure, in degrees, of $\angle CAB$?
