title: Invoker ultimate(DOTA 2) combination... How is it calculated?
body: <p>While playing DOTA 2 with invoker I thought how the total combination of his ultimate calculated.</p>
  
  <p>Description:</p>
  
  <p>He has 9 element. lets say 3(blue) , 3 (pink) and 3(yellow) . Every time he can choose 3 element from there. How many way is there to pick? Answer is 10. I didn't get it.</p>
  
  <p>A dumb question to start with sorry for that.</p>
  
  <p><a href="https://i.stack.imgur.com/G6m6a.jpg" rel="nofollow noreferrer">Here is the picture with all combination</a></p>