Complete each expression showing all steps, and simplify the final answer to lowest terms (improper fractions do not need to be changed to mixed numbers as in grade 9, we work with improper fractions instead).

White shapes and black shapes are used in a game. some of the shapes are circles. while the rest are squares. the ratio of the number of white shapes to the number of black shapes is 5: 11. the ratio of the number of white cicrles to the number of white squares is 3: 7. the ratio of the number of black circles to the number of black squres is 3: 8. work out what fraction of all the shapes are circles.