Unless 0.5 is a typo and it should have actually read 0.25. Then the last line makes more sense too. Except of course 20/0.25 = 80x and not 20x as claimed in st

Unless 0.5 is a typo and it should have actually read 0.25. Then the last line makes more sense too. Except of course 20/0.25 = 80x and not 20x as claimed in step 4... But never mind, it's a fun post.