title: EXCEL How do I summarize a list?
body: <p>I am going to do my best to explain what I have and what I need.</p>
  
  <p>I have a list of wood pieces (length x width) that I want to summaries in order to have the pieces quantity of every type of piece.</p>
  
  <p>For example</p>
  
  <p>This list has 3 columns (Colum A Colum B and Colum C) </p>
  
  <p>Colum A shows the length</p>
  
  <p>Colum B shows the width</p>
  
  <p>Colum C shows the quantity </p>
  
  <p>And in the list, the same type of piece can be shown few times and whit different quantities. </p>
  
  <p>Looks like this</p>
  
  <p>10x10 1</p>
  
  <p>10x10 4</p>
  
  <p>20x40 6</p>
  
  <p>30x40 1</p>
  
  <p>30x40 5</p>
  
  <p>20x40 3</p>
  
  <p>I’m looking for a solution that can help me to:</p>
  
  <p>SUM the quantity shown in Colum C for the same type of wood piece. </p>
  
  <p>The solution for this example is next.</p>
  
  <p>10x10 5</p>
  
  <p>20x40 9</p>
  
  <p>30x40 6</p>
  
  <p>clik for the example image <a href="http://i.stack.imgur.com/jC7Oq.png" rel="nofollow">EXAMPLE</a></p>