title: 2 4-bit binary multiplication in excel
body: <p>Using excel to demonstrate 4-bit x 4-bit binary multiplication as follows:</p>
  
  <ol>
  <li>Convert the multiplier to binary and process one bit at a time</li>
  <li>All other operations can be done in decimal.</li>
  </ol>
  
  <p>I have the above question for homework, but it has been given to me by a poor teacher with poor notes. Can anyone give me an idea of where I can read up on the topic? Are there any books (or preferably a link to a webpage) that I could read up on to help me with it? </p>
  
  <p><img src="https://i.stack.imgur.com/MVKhO.png" alt="image"></p>
  
  <p>This is what I have so far. Obviously it's wrong. The thing I'm having trouble with is the addition of the products. I can't simply use =sum() because it 1+1 should equal '0' with a carry. How do I go about achieving this?</p>
  
  <p>Any advice welcome. Thanking you in advance.
  Joe.</p>