Lana has 3 bags with the same number of marbles in them, totaling 384 marbles. Mark has 7 bags with the same number of marbles in them, totaling 945 marbles. How many more marbles does Mark have in each bag?
Lana has 384/3 = <<384/3=128>>128 marbles per bag.
Mark has 945/7 = <<945/7=135>>135 marbles per bag.
Mark has 135 - 128 = <<135-128=7>>7 more marbles in each bag. Answer: \boxed{7}.