<p>I'm not sure that your question deserves two downvotes.  Your question is from a course or textbook, so it qualifies as 'homework' for our purposes.  You should add the <code>[self-study]</code> tag &amp; read <a href="https://stats.stackexchange.com/tags/self-study/info">its wiki</a>.  That said, you certainly don't hide that fact, and aren't just after the answer / someone to do your homework for you.  You do tell us what you understand thus far, what you've tried &amp; where you're stuck, which is what we request.  </p>

<p>One other possible issue is that you present an image of the question, rather than retyping the question as text.  You should do so instead of just posting a photograph (see <a href="https://stats.meta.stackexchange.com/a/3176/">here</a>). </p>

<p>You could also use a better title, as @mkt <a href="https://stats.stackexchange.com/questions/336994/probability-a-new-treatment-for-a-disease-is-being-tested-to-see-whether-it-is#comment636942_336994">suggested</a>.  </p>
