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title: "Numbers Held Inexactly in the ZX81 (Part 2)"
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excerpt: "Second part of the series on ZX81 floating-point representation, focusing on positive integral powers of 10. Explains that powers of 10 from 10 to 1E13 are held exactly, while 10**N forms are slightly inaccurate. Includes method for manually verifying accuracy."
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  - name: "Frank O'Hara"
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volume: "3"
issue: "4"
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    title: "Syntax/Syntax ZX80 v3 n4"
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pages: "3"
pubdate: "April 1982"
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---

# Numbers Held Inexactly in the ZX81 (Part 2)

Second part of the series on ZX81 floating-point representation, focusing on positive integral powers of 10. Explains that powers of 10 from 10 to 1E13 are held exactly, while 10**N forms are slightly inaccurate. Includes method for manually verifying accuracy.