Answer: 20.5
Step-by-step explanation:
From the measure of the length of the sides of the triangle, 9, 40 and 41 we can infer that the triangle is a right angled triangle. 9-40-41 is a Pythagorean triplet.
In a right angled triangle, the circumradius is half the hypotenuse.
In the given triangle, the hypotenuse = 41.
Therefore, the circumradius is 41÷2= 20.5 units.