



 
Hi there. When dealing with flat objects, the ratios of area dimensions are the square of the linear dimensions on similar (scaled) objects. For example, a circle whose diameter is 3 units has an area of 2.25π. A circle whose diameter is 12 would have an area 16 times as large (because 12/3 is 4 and 4^{2} is 16). Another example: Two maps of the same region are available at different scales. In the first map, a farmer's field is 100 millimeters squared. In the second map, the same field is 2500 millimeters squared. What is the ratio of their perimeters? Answer: sqrt(2500/100) = 5:1. Hope this helps,  


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