Rosemary should use 5 times the amounts in the recipe, since she needs 200 cupcakes. As such, she'll require 5*6=30 cups.
Since Russell uses a bit more, 10% more flour, he'll need 110% of 30 cups for the same amount of cupcakes, so he'll need: 1.10*30=33 cups of flour.
In total, the whole project will require 30+33= 63 cups of flour