Decimal To Fraction

Do you need to convert a decimal to a fraction or back the other way?
This will explain how to convert:
Decimals to Fractions
AND
Fractions back to Decimals

Step 1 The conversion

To convert a decimal to a fraction you need to know what each place in a decimal equals.
_{see the chart below}
To make it easier think of it this way:
the ones place is x/1, place just to the right of the decimal is x/10, the next place to the right is x/100, etc...
For each place the you move to the right of the decimal add another zero (0) to the denominator.

so 0.5 = 5/10, 0.006 = 6/1000, 0.0004 = 4/10000

Comments

[Jack A Lopez]

Very nice instructable, but I can think of a way to make it nicer. You mention repeating decimals, but you don't tell us how to convert a repeating decimal to a fraction.

All repeating fractions have (10^{n-1) for the denominator, and the repeating part for the numerator, where n is the length of the repeating part.}
Example:
0.12871287128712... = 1287/9999 = 13/101

[ggiihh1]

(removed by author or community request)

[Jack A Lopez]

I don't know if that would be "legal" wrt contest rules, or not?

Maybe one of the instructibles elders reading this could comment? I'm just a noob here really.

I would think it would be legal to make edits to your ible up until the deadline of the contest, but that's just a guess. As far as using my suggestions, I hereby give you permission to use whatever intellectual "stuff" I've given you, licence-free, and you don't have to a attribute it to me either.

Also I think maybe I just made that comment to show off a little bit, without the large amount of work of writing a whole instructible myself. That'd probably be the ethical way for me to show off my math smarts.

And of course, while I was trying to be smart the editor screwed up the formating. I was trying to write the denominator is (10ⁿ -1), not 10^(n-1) followed by a bunch of small superscripted text.
;-)

[Goodhart]

Very nice instructable, and useful too. Very well explained.

[ggiihh1]

(removed by author or community request)

[Goodhart]

Think I should make an instructable converting decimals to percentages?

Sure, if you can make is as well organized as this one (also note the first few of Kiteman's Laws ;-)