It is: 2 to 3
12
12
If you mean: 8 12 16 and 10 15 20 then it is 4 to 5
Assuming the smaller sphere is the image of the larger sphere after transformation (based on the order of the radii): the scale factor is 4/12 = 1/3
It is: 21/12 = 7/4
Length of image = Length of original*Scale factor = 10*8 = 80 yards.
Answer: Since you are looking for the scale factor of ABC to DEF the answer is 8 because DEF is 8 times larger than ABC.
It is: 3 to 2
2:3
The greatest common factor of 8, 10, and 12 is 2.
12