Question

What is the radius if the Diameter 10.5?
r = 8.5
r = 5.25
r = 12.5
r = 21

Answer 1

If the diameter is 10.5 then the radius is 5.25.
This is because the radius of a diameter is half the diameter.

So

10.5/2
= 5.25

Therefore the radius is 5.25