Speaker front baffle with multiple and equal speaker holes at equal distance

Hi! 

Newbie here. Designspark looks brilliant in its 3d part, but I am striving a bit with the 2d drawing, as follows:

For a speaker baffle with N equal speaker drivers with a fixed distance D between each hole, how is this easily done? From power point, I am used to features like "evenly distribute selected items" (based on the position of the first and the last item), but I cannot figure out how to achieve something similar here. So the question is: What's the easy way to create 10 holes in a 2D drawing, all at equal distance, and grouped so that I may "drag" the whole group and thus expand or diminish the distance between each hole, while keeping the radius of each hole?

The number N in this case is actually a total of +50 holes, thus, I hope to avoid to make each one manually. I am aware of the "mirror" feature which would reduce the job to 25, but anyway.

Thanks for any hints on this. (After studying many video tutorials).