Polly has three circles cut from three pieces of coloured card. She originally places them on top of each other as shown. In this configuration the area of the visible black region is seven times the area of the white circle. Before After Polly moves the circles to a new position, as shown, with each pair of circles touching each other. What is the ratio between the areas of the visible black regions before and after?
Select one option, then click Submit.
3 : 1
4 : 3
6 : 5
7 : 6
9 : 7
Select an option, then submit.
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