Need help with 16, 17, 18 quickly pls ​

Math each whole number with a rational,exponential expression

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.

Avideo game enthusiast saved $750 to spend on a video game player and games. the player costs $400. the games costs $49 each. at most how many games can this enthusiast buy along the player