A bag contains 30 red marbles and 15 purple marbles. Mr. Clark wants to add 270 marbles to the bag. He wants the ratio of red to purple marbles to remain the same. How many of each should he add? A. 70 red marbles 200 purple marbles B. 200 red marbles and 70 purple marbles C. 180 purple marbles and 90 red marbles D. 180 red marbles and 90 purple marbles