title: Calculating total transmission time of a packet
body: <p>I'm having some difficulty calculating the total time it takes a packet to get from A to B, the question is:</p>
  
  <p>"We have 200 bytes of data to send from A to B, with a distance of 200km between them. Calculate the total transmission time, assuming the speed of the signal is 200,000 km/s and that the data rate is 1Mbps and that a header of 40 bytes has to be added to the data before it is sent."</p>
  
  <p>My understanding is that at some point you need to factor in propagation and the speed of light (??) but I'm unsure if it's needed in this case. Is there a formula which can be used to work these types of question out?</p>