At what distance I see the Moon

A simple calculation that I did to know what distance I am from the Moon while watching through a telescope, it appeared this:
-telescope data:
          -focal length: 1,000 mm
          -eyepiece: 20 mm.
          -Barlow lens: 2x
          -video camera optical zoom: 10x
-Calculation: -1000:20 x2 = 100 (or 100x)
                        -100x10 = 1000 (or 1000x)
        If the Moon is approx. 400,000 kilometers from the Earth, it means that:
                         400.000:1000 = 400 (that I am at 400 km above the Moon)
If you replace the data with an eyepiece of 10 mm instead of 20 mm, and the other data to be the same, it follows that I would approach the Moon with another 200 km. Am I right?

Posted in: Things about the Moon