I am looking at the Rokinon 35mm T1.5 and speedbooster for my m43 Panasonic GH3. I am trying to get a 50mm equivalence on full frame and my math is 35mm x 2 = 70 and then 70 x .71 (focal length of speedbooster) - 49.7mm, which for all effective purposes is a 50mm. Is this correct?

Someone else has tried this already on the forum, and it is a heck of a combination. See here: https://www.mu-43.com/showthread.php?t=68723