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A comment on 0.30000000000000004. Parent comment

Re:0.30000000000000004 by jayceekay on Friday November 13, 2015 @12:29PM (#10561036)
> In contrast, 1/3, 1/6, and 1/7 are all repeating decimals because their denominators use a prime factor of 3 or 7.

doesn't 1/6 use a prime factor of 2 as well?

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Re:0.30000000000000004 by such_a_casual on Friday November 13, 2015 @12:59PM (#10561242)
In the fraction 1/6, the prime factors of the denominator are 2 and 3. A base 10 number system has the 2 but not the 3.
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Re:0.30000000000000004 by jayceekay on Saturday November 14, 2015 @07:06PM (#10567866)
got it, thanks!
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Re:0.30000000000000004 by thedufer on Friday November 13, 2015 @12:46PM (#10561154)
Yes, but in order to have a non-repeating decimal expansion, the denominator must share _all_ of its factors with the base. That is, only fractions that, when reduced, have a denominator of the form 2^n*5^m (for natural numbers n, m) will terminate in base 10. The explanation given could probably be clearer.
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Re:0.30000000000000004 by jayceekay on Saturday November 14, 2015 @07:06PM (#10567864)
ah yes, the _all_ is what i missed. thanks.
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