How to pronounce “one eighth” in English

And in it, terrorists steal one eighth of a gram of antimatter from CERN to try to blow up the Vatican.

And it's a passage that talks about the size of your head should be about one eighth of the size of your body,

That's because that's what it is, because she knows that extra scant one eighth of a cup makes the magic happen.

We walked out over the East River, hitting the deck whenever a train came by, and made it about one eighth of a mile from the Brooklyn shore

channel because you can't keep it cool anymore, what do you do when your station is now at one eighth less power?