Bayes Rule!

My question is:

A company wishes to evaluate the effectiveness of a marketing campaign.
Seventy-five percent of all customers using the product were reached in a
focused advertising campaign. Twenty-eight percent of those reached through
the campaign purchased the product while 8% of the purchases came from
customers who did not receive the targeted advertising campaign. Answer the
following questions:

What is the probability a professor who adopts a book received the advertising material?

I've been told the answer is 0.91 but cant seem to get to it

Thanks in advance for any help!!!


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Hi! :welcome: We are glad that you posted here! This looks like a homework question though. Our homework help policy can be found here. We mainly just want to see what you have tried so far and that you have put some effort into the problem. I would also suggest checking out this thread for some guidelines on smart posting behavior that can help you get answers that are better much more quickly.