title: How do I add two hexadecimal values?
body: <p>this is a school assignment. I've been given homework and one of the problems is to figure out the value after adding two hexadecimal values.   </p>
  
  <p>0x80000000 and 0xD0000000. I understand that D = 13, but I don't understand how the answer is 15, because 8 + 13 = 23? Could someone explain what I am doing wrong, and what I should do instead?</p>
  
  <p>Thanks!</p>