So the question is to find the areas A - G.
You are told that the vertical length is 4 and horizontal length is 28
I started making a load of simultaneous equations but found there was too many variables that left me not being able to solve what first appeared to be a straight forward question.
Does anyone know of a simpler route forward? Or is it just identifying which simultaneous equations need using when?

Hint:
$10: 2$ as $5: G$. That type of thinking should get you there.
More hints: