geometric unsharpness is fixed by setting the focal radius,etc.

while radiographic unsharpness consists of both geometric and film unsharpness.

The finite size of the focal spot results in divergence of the beam beyond the magnified image of the object (creating an area called the penumbra). This is termed focal spot or geometric blurring and results in reduced image resolution. In the absence of magnification (that is, the image is adjacent to the receptor) there is no focal spot blurring.

Geometric

There aren't any. Geometric is an adjective and you need a noun to go with it before it is possible to consider answering the question. There are geometric sequences, geometric means, geometric theories, geometric shapes. I cannot guess what your question is about.

If, by geometric number (?) you mean geometric mean, then the answer is 40.