.
A magazine surveyed 100 readers about whether they had read a certain novel or
watched its movie adaptation.
The data collected is represented in the Venn diagram below.
(46 in Movie) (17 in movie and novel) (34 in novel) (3 have watched and read neither).
A reader was selected at random. If the reader selected has watched the movie,
what is the probability that they have also read the novel?
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Actually, your wording description in this post is INCORRECT.
Usually/traditionally, when Venn diagram is presented and described in words,
when you say X are in movies, it means that X includes
+---------------------------------------------+
| (those 46 that are in movie only) |
| PLUS (those 17 that are in BOTH), too. |
+---------------------------------------------+
But in your post, these 46 plus 17 plus 34 are disjoint separate categories,
without explicit notification.
It tells me that the problem is composed by a person , who does not know
the rules on how to describe Venn diagrams.
I do not know, if the composer did it intently to confuse the reader
or because he (or she) simply does not know the subject.
But in any case, the description in the post is incorrect.
To be correct, it must say at the very beginning that the list describes
separate disjoint categories, and do not use the term " Venn diagram ", at all,
because it is IRRELEVANT.
At this forum, I used to see unprofessionally written Math problems every day,
so it does not surprise me.