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If r and s are positive integers, can the fraction r/s be expressed as
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26 Apr 2015, 12:24
Hi
In the question p/q, how can we be sure whether this can be reduced or it is already reduced
Also, if the first option would have been a multiple of 100 then the option would have been insufficient right? Since we could have any other prime factor



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If r and s are positive integers, can the fraction r/s be expressed as
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26 Apr 2015, 12:48
kirtivardhan wrote: Hi In the question p/q, how can we be sure whether this can be reduced or it is already reduced If we have only this information, we can't say nothing about state of this fraction. And if we have information only about \(r\) or about \(q\) it's the same: we can't say nothing about reducing of this fraction. I think I've got your previous question. Yes this task is exception about reducing factors: because in this case we need to know if denominator contain any other factors except \(2\) and \(5\). and we already have information that denominator is a factor of \(100\), so we know that denominator doesn't conatain any factors except \(2\) and \(5\) and we don't need to reduce fraction. kirtivardhan wrote: Also, if the first option would have been a multiple of 100 then the option would have been insufficient right? Since we could have any other prime factor Absolutely right.
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Re: If r and s are positive integers, can the fraction r/s be expressed as
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05 Nov 2015, 04:36
''as a decimal with only a finite number of nonzero digits'' what does it exactly mean? Are 3.05, 9.002 etc under this category or sth else?



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Re: If r and s are positive integers, can the fraction r/s be expressed as
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05 Nov 2015, 11:22



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Re: If r and s are positive integers, can the fraction r/s be expressed as
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08 Nov 2015, 06:32
Forget conventional ways of solving math questions. In DS, Variable approach is the easiest and quickest way to find the answer without actually solving the problem. Remember equal number of variables and independent equations ensures a solution. If r and s are positive integers, can the fraction r/s be expressed as If r and s are positive integers, can the fraction r/s be expressed as a decimal with only a finite number of nonzero digits? (1) s is a factor of 100 (2) r is a factor of 100 This is a commonly tested type of question. If we modify the question, we get a decimal with only a finite number of nonzero digits=terminating decimal. So, it is referring to things such as 0.2=1/5, 0.5=1/2, 0.21=21/(2^2)(5^2). But in order to become a terminating decimal, the denominator has to have 2 or 5 as their prime factors; as the question asks whether the prime factor of s is composed of only 2 or 5 in r/s, we only need to know the value of s. In condition 1, 100=(2^2)(5^2). The prime factors only include 2 or 5, so the condition is sufficient and the answer becomes (A). Once we modify the original condition and the question according to the variable approach method 1, we can solve approximately 30% of DS questions.
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Re: If r and s are positive integers, can the fraction r/s be expressed as
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24 Jul 2016, 04:42
The question asks if r/s can be expressed as a decimal with only a finite number of nonzero digits. So, it's asking if r/s can be expressed with a finite number of nonzero digits and nothing else (therefore, there can be no zeroes in the decimal). So, 10, for example, would not work (there's a zero in 10).
Or are we supposed to read the "only" to refer only to the "finite number" part of the question?



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Re: If r and s are positive integers, can the fraction r/s be expressed as
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24 Jul 2016, 08:07



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If r and s are positive integers, can the fraction r/s be expressed as
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24 Jul 2016, 09:29
Bunuel wrote: momonmoprob wrote: The question asks if r/s can be expressed as a decimal with only a finite number of nonzero digits. So, it's asking if r/s can be expressed with a finite number of nonzero digits and nothing else (therefore, there can be no zeroes in the decimal). So, 10, for example, would not work (there's a zero in 10).
Or are we supposed to read the "only" to refer only to the "finite number" part of the question? "Only" refers to finite, only. I find that a bit confusing, is there some way I can avoid this confusion in the future? To me the wording is pretty clear, the decimal should only have a finite number of nonzero digits, in which case there should be a finite number of nonzero digits and nothing else (no zeroes). How are we supposed to know during the test what they mean? EDIT: Further, if they meant for the "only" to refer to "finite," only, then they simply should have wrote the question as "...can r/s can be expressed as a decimal with a finite number of nonzero digits?" That would have gotten the intended message across.



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Re: If r and s are positive integers, can the fraction r/s be expressed as
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24 Jul 2016, 12:52
momonmoprob wrote: Bunuel wrote: momonmoprob wrote: The question asks if r/s can be expressed as a decimal with only a finite number of nonzero digits. So, it's asking if r/s can be expressed with a finite number of nonzero digits and nothing else (therefore, there can be no zeroes in the decimal). So, 10, for example, would not work (there's a zero in 10).
Or are we supposed to read the "only" to refer only to the "finite number" part of the question? "Only" refers to finite, only. I find that a bit confusing, is there some way I can avoid this confusion in the future? To me the wording is pretty clear, the decimal should only have a finite number of nonzero digits, in which case there should be a finite number of nonzero digits and nothing else (no zeroes). How are we supposed to know during the test what they mean? EDIT: Further, if they meant for the "only" to refer to "finite," only, then they simply should have wrote the question as "...can r/s can be expressed as a decimal with a finite number of nonzero digits?" That would have gotten the intended message across. Hello momonmoprobThe phrases "with only a finite number of nonzero digits" and "with a finite number of nonzero digits" are equal. "To me the wording is pretty clear, the decimal should only have a finite number of nonzero digits"this is not correct because the word "only" can not modify words and do not stand next to them: "with only a finite number of nonzero digits"  here word " only" modifies " finite number" "with a finite number of only nonzero digits"  here word " only" modifies " nonzero digits"
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Re: If r and s are positive integers, can the fraction r/s be expressed as
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13 Jan 2019, 17:57
What if r=25 and s=25
Then 25/25=1
It has no decimal point in this case.
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Re: If r and s are positive integers, can the fraction r/s be expressed as
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13 Jan 2019, 21:16



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Re: If r and s are positive integers, can the fraction r/s be expressed as
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28 Feb 2019, 02:25
Quote: 1)S is a factor of 100. So S cannot have more than two 2s and two 5s. Any number divisible be 2 or 5 gives a finite decimal. Since R and S are both positive integers, there can be no 0s in the decimal places either. So Sufficient MacFauzIf r=1, 1/100 is a possible answer as 100 is factor of 100. 1/100= 0.01 which has a zero in a decimal place. Hence, your conclusion doesn't work 100% times. Am I right?



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Re: If r and s are positive integers, can the fraction r/s be expressed as
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02 Mar 2019, 09:59
I have trouble understanding "a decimal with only a finite number of nonzero digits". 0.01=1/100, but there is a zero in the decimal digits.




Re: If r and s are positive integers, can the fraction r/s be expressed as
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