title: How to use norm.ppf()?
body: <p>I couldn't understand how to properly use this function, could someone please explain it to me?</p>
  
  <p>Let's say I have:</p>
  
  <ul>
  <li>a mean of 172.7815</li>
  <li>a standard deviation of 4.1532</li>
  <li>N = 50 (50 samples)</li>
  </ul>
  
  <p>When I'm asked to calculate the (95%) margin of error using norm.ppf() will the code look like below?</p>
  
  <pre><code>norm.ppf(0.95, loc=172.78, scale=4.15)
  </code></pre>
  
  <p>or will it look like this?</p>
  
  <pre><code>norm.ppf(0.95, loc=0, scale=1)
  </code></pre>
  
  <p>Because I know it's calculating the area of the curve to the right of the confidence interval (95%, 97.5% etc...see image below), but when I have a mean and a standard deviation, I get really confused as to how to use the function.</p>
  
  <p><a href="https://i.stack.imgur.com/aoR9U.png" rel="noreferrer"><img src="https://i.stack.imgur.com/aoR9U.png" alt="enter image description here"></a> </p>