The ZX81 doesn't hold simple decimals like .5 & .25 exactly.
Numbers Held Inexactly on the ZX81, Part 4 AuthorsFrank O'HaraPublicationSyntaxPub DetailsSyntax/Syntax ZX80 v3 n6Volume: 3 Issue: 6DateJune 1982Pages19-20Read the articleSee all articles from Syntax/Syntax ZX80 v3 n6 The ZX81 doesn’t hold simple decimals like .5 & .25 exactly. Tags1982 TS 1000 Type-in program ZX81 PeopleFrank O'Hara