title: Extracting values from string -> group result
body: <p>I would like to extract some decimal numbers in a string -> group the strings and sum the values.</p>
  
  <p>I get the strings from a private API. They look something like this:</p>
  
  <pre><code>var foo = new List&lt;string&gt;()
                {
                    "+0.9 A / +0.62 B",
                    "+0.9 A / +0.62 B",
                    "+0.9 A / +0.62 B",
                    "+1.2 C",
                    "+1.2 C",
                    "+2.0% D",
                    "+2.0% D"
                }.GroupBy(x =&gt; x).ToList();
  
  foreach (var group in foo)
  {
      foreach (var str in group)
      {
          //...?       
      }
  }
  </code></pre>
  
  <p>Desired result:</p>
  
  <pre><code>"+2.7 A / +1.86 B",
  "+2,4 C",
  "+4.0% D"
  </code></pre>
  
  <p>I guess that this has to be solved using regex. I don't know how to create a pattern,  but my best bet is something like <code>\+\d+\.?\d*</code>. It might be on the right track, but I need your help finishing it. For example, it doesn't take the possible "%" in to consideration ("+2.0%").</p>