Y - 15 = -15 what's the answer

When y’all answer can y’all explain too !

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.

The distance between two points is 6.5cm and scale of map is 1: 1000 what's the distance between the two points