A circle has 3.8 cm What is the radius?

Radius in from the center of circle or sphere, so a radius of 3.8 cm is a diameter of 7.6cm and circumference 23.8 cm (or 24 cm).

Or

If you mean 3.8 is the diameter (width), then radius is half (1/2) which equals 1.9 cm and circumference of 11.9 cm (12cm).

Or

If circumference 3.8 then radius is 1.2cm and area is 1.152cm.

I hope this answers your question.

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