Select the best answer for the question, 18. Which one of the following statements expresses a true proportion?
O A. 3:4 = 9:12
O B. 7:9 = 8:9
O C. 54:9 = 6:3
O D.21 = 12
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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.