The diameter of circle A is 4.8. The correct option is the second option- 4.8
From the question, we are to determine the diameter of circle A
From the given information,
Circle A is dilated by a scale factor of 2.5 to form circle B
That is,
If the diameter of circle A is d, then the diameter of circle B will be 2.5d
Also, from the given information,
Diameter of circle B = 12
Then, we can write that
2.5d = 12
∴ d = 12/2.5
d = 4.8
Hence, the diameter of circle A is 4.8. The correct option is the second option- 4.8
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