Which is the intersection of the sets {2,3,5,7} and {2,5,11,13}? a. null set b.{2,3,5,7,11,13} c.{2,5} d.{3,7,11,13}

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.