I need explanation i already know answer Jack k buys four apples.
He pays with a £2 coin.
He gets £1.20 change.
How much does one apple cost? Ans=20p

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.