you can see how to set this up here. Since they give Pa's speed in terms of Ra's speed, pick a variable for Ra's speed and then do an expression for Pa's speed. Go from there, using d=rt w/ d=315 and the stuff you just did for r.Distance betw NY and Paris is 315miles. Ra and Pa leave NY at same time. However Pa arrives in Paris 1hr 10mins before Ra with an avg speed that was 9 miles per hr faster. how fast was each traveling ?