The answer is 24.5. Just plug the numbers in
Let x be the amount of cocoa you use in the recipe.
then 4x is the amount of flour used, and 5x is the amount sugar used.
x+4x+5x= 550g
10x=550g
x=55g
So, you use 55g of cocoa, 220g of flour, and 275g of sugar.
hope this helps! :)