title: Tableau calculation with attributes
body: <p>I'm new with tableau and I try to calculate with different attributes from one dimension and one measure. 
  <a href="https://i.stack.imgur.com/AiA3n.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/AiA3n.png" alt="enter image description here"></a></p>
  
  <p>I want to calculate the sum of the attributes RC,RD and RP and divide this by RI. I would be very thankfull if you can help me.</p>