Answer: Yes there proportional:)
Explanation:
The diameter of a circle is twice the length of the radius, so if the diameter of a circle is proportional to the radius, then the diameter will be equal to twice the radius.
The ratio of the radius of the circle with a diameter of 100 mm to the radius of the circle with a diameter of 10 mm is 50 mm / 5 mm = 10.
The ratio of the diameters of the two circles is 100 mm / 10 mm = 10.
Since the ratio of the radius to the diameter is the same for both circles, the radius and diameter of both circles are proportional.