An air traffic controller is tracking two planes. To start, Plane A was at an altitude of 990 meters, and Plane B was at an altitude of 1476 meters. Plane A is losing altitude at 18 meters per second, and Plane B is losing altitude at 27 meters per second.
Let x be the number of seconds that have passed

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.