Students within the department of mathematics and statistics fall into one of three categories: undergraduate, postgraduate or doctoral, as shown in the table below. Express the number of students in each category as a percentage of the total number of students within the department. (6) Category Number of students Undergraduate 188 Postgraduate 42 Doctoral 19

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.