Cate and elena were playing a card game. the stack of cards in the middle had 24 cards in it to begin with. cate added 8 cards to the stack. elena then took 12 from the stack. finally, cate took 9 cards from the stack. how many cards were left in the stack.

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.