It is a well known fact that if in a fraction,the denominator is of the form 2m∗5n where m and n are non−negative integers the fraction has a terminating decimal.
Here is the proof:
Let us say that there is a fraction in which the numerator is N and the denominator be 2m∗5n where m+n=x
The fraction can be written as:2x−n∗5x−mN
Multiplying by 2n2n and then by 5m5mwe have a fraction which has a new numerator,let us call it A.\
The new denominator is 10xThus,the new fraction is 10xA.\ Which,obviously,has a terminating decimal expansion.
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@Krishna Ar
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WOW @Krishna Ar, this is called popularity!
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hehe
-_-
(y)
Nice note, Adarsh. You may also like to add the number of decimal digits after a number of such a form terminates. It's closely related to your proof. Also, you don't need to latex the whole thing. If you are using a latex editor, then there's no need. If you want to learn it, you can easily do so here. Thanks.
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thanx.But I recently learned LATEX and now I can't get enough of it.
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BTW which class r u in?
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I don't understand "I can't get enough of it", you can always learn it. It's really easy to learn.
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Do you have the proof of the property of recurring decimal expansions that they repeat for n-1 digits in a fraction 1/n?
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That's not necessary. It is only true in case of cyclic numbers. I was referring to the number of after-decimal digits after 2m5nx terminates. It's the larger of m and n.
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It is a very simple proof which was in my RD SHARMA but I thought it too elegant not to share it with you guys.
expect the unexpected !