There are three choices for Mrs. Stanton. One of the three choices is the Women's Day magazine. Thus, 1 out of 3, or 1/3 of the choices are Women's Day.
I think your question needs to be worded differently. The tangents would intercept a major arc (204) and a minor arc (156). The angle formed would be one half of the major arc. The angle would measure (1/2) (204-156) = 24 degrees