Get the real life measured distance from ArUco markers

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Hello. My problem is that I am detecting ArUco markers. Two markers are detected and difference between the markers centers are 2.45 cm. From one or two markers, I want to know what is the distance between the camera and one of the marker. I will use it for drone landing. I thought I can do it with 2 markers. But nothing comes to mind. Is there any way to do it? Looked at some posts but not quite I want, they are not answered also.

More deeper, I want to know how a translation vector describes 3D world and can I get an information with that. For example, if the vector is [1,1,3], can I get the distance with multiplying an X number by 3 ? Thanks in advance.