



 
Hi Maisy, The one fact you need to know is that the circumference of a circle is $2 \pi \;r mbox{ miles}$ where $r$ is the radius in miles. In my diagram the quarter circle, coloured yellow, has a perimeter, coloured red, in three sections. Two of them are radii of the circle and the third is 1/4 of the circumference of the circle. Penny  


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