Question: I have a concrete floor and I made two holes to bolt a 1/4"-thick steel plate. The problem is that the steel plates haven't been drilled yet.

How can I determine where the holes will be drilled in the steel plates so they match the holes in the concrete?
[![enter image description here](https://i.stack.imgur.com/1Kt5n.png)](https://i.stack.imgur.com/1Kt5n.png)

Answer: 
If you have a laserpointer (or 2) "hang them" (they should not move around of course) above if possible so they point down vertically into the center of the hole(s). Put the steelplate in position and the laser marks the spot(s).
Tape one side of a piece of paper onto the concrete and trace the holes, then put the steel plate under the piece of paper and center punch the holes onto the steel plate.