A circle has a radius of 3 feet. what is the circumference of a bigger circle if the scale factor of the smaller to bigger is 4:7? Then, what would be the ratio of the circumference from the larger circle to the smaller circle?

Step-by-step explanation:

b) The problem statement tells you the ratio of linear dimensions (radius or circumference) is ...

   larger/smaller = 7/4

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a) The circumference of the smaller circle is ...

  C = 2πr = 2π(3 ft) = 6π ft

Then the circumference of the larger circle is ...

  (7/4)(6π ft) = 21π/2 ft . . . . . larger circumference

21

step-by-step explanation:

geometry: triangles

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call the larger triangle abc

then the smaller triangle cde is similar to abc (all angles are equal, aaa).  

ab is the side that is 36, and we wish to find de, the side corresponding to ab

area_cde = area_abc - area_cde --> area_abc / area_cde = 2

let x=length of de

ratio of areas = (ratio of sides)^2

+2+=+%2836%2fx%29%5e2+

+2+=+1296%2fx%5e2+

++x%5e2+=+1296%2f2+=+648+

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