Confused by the Confuser? surely not!
In fairness, that book has been out of print for a while now, either the PPL perfector or PPL simplifier seem much better.
In the real exam they don't tend to put 3 legs into one question, and they will give you all the info you need.
The fact you are finding a completed plog in the confuser, that is probably the one you're meant to refer to to check your answers. There may be a partially completed one elsewhere in the book which you are meant to use to actually do the answer. Worth double checking.