The question is a little confusing. I would probably say multiplication? You need to divide both by 6, because she wants 6 pieces to fit into both values. So 66/6=11 and 36/6=6. Then I suppose a subtraction to find the difference, which would be 11-6=5, so 5 inches difference between one piece of pink and one piece of white. Hope I got this right and that was actually what the question was asking haha. Sorry if not