The same question is in the discussion section in ExplainXKCD, so I can confidently use the reply given there: No, 7/20" is the radius, but 7/10" is correct for the diameter.
Comment on Globe Safety
abfarid@startrek.website 4 days ago
Shouldn’t 7/10" actually be 7/20"?
Gieselbrecht@feddit.org 4 days ago
abfarid@startrek.website 4 days ago
Oh right, didn’t pay enough attention. But it was the first thing I saw in the morning.
EmptySlime@lemmy.blahaj.zone 4 days ago
Notice how the lines the 7/10" is attached to go from one side of the miniature globe to the other? This indicates that measurement is meant to be a diameter. Looking back at the paragraph before he talks about 0.35" being Earth’s Schwarzschild Radius. Radius is half of diameter so doubling that radius you get 0.7 or 7/10" across at which the Earth would become a black hole.
That’s what that mini diagram is showing.
vivendi@programming.dev 4 days ago
What in the motherfuck are those numbers
What the fuck is wrong with your units
LanguageIsCool@lemmy.world 3 days ago
They’re literally called rational numbers