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If p, s, and t are positive integer, is ps  pt > p(s  t) ? [#permalink]
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18 Dec 2015, 13:11
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If p, s, and t are positive integer, is ps  pt > p(s  t) ? (1) p < s (2) s < t
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Re: If p, s, and t are positive integer, is ps  pt > p(s  t) ? [#permalink]
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18 Dec 2015, 13:18
ajayvyavahare wrote: If p,s, and t are positive integer, is pspt > p(st)
(1) p < s (2) s < t
need help to solve this one. Do not forget to mention the source of the question.it is simple after you realise that as p is positive, you can rewrite the given inequality as pspt > p(st) = pst > p(st) , you can also remove 'p' from both the sides , leaving you with is st > st which is very clearly obtainable if you know about the relative relation between t and s (side note, not required for this question: for st > st to be true, this means that st<0 or s<t)Statement 1, gives no information about relation between t and s , hence not sufficient. Statement 2, gives the exact relation we need to answer the question and as such is sufficient. B is the correct answer. Hope this helps.



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Re: If p, s, and t are positive integer, is ps  pt > p(s  t) ? [#permalink]
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19 Dec 2015, 05:43
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 p,s, and t are positive integer, is pspt > p(st)? (1) p < s (2) s < t When you modify the condition and the question, pspt > p(st)?> pspt<0?, therefore p(st)<0?. Since p>0, you need to find out st<0?. In 2), st<0, which is yes and sufficient. Therefore, the answer is B. > 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 p, s, and t are positive integer, is ps  pt > p(s  t) ? [#permalink]
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19 Dec 2015, 06:39
ajayvyavahare wrote: If p,s, and t are positive integer, is pspt > p(st)
(1) p < s (2) s < t
need help to solve this one. Hi, the eq is pspt > p(st).. or plstl > p(st) since all numbers are positive , p cannot be 0.. two instances.. 1) lstl will never be smaller than st as lstl will always be positive while st will depend on relative values of s and t.. 2) if s and t are equal both will be 0.. so our answer for pspt > p(st) will be NO if s>t or s=t.. and it will be YES if s<t... so we are just looking for the relation between s and tlets see the statements.. (1) p < s... nothing between s and t.. insuff (2) s < t answer is YES.. suff ans B
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Re: If p, s, and t are positive integer, is ps  pt > p(s  t) ? [#permalink]
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06 Oct 2016, 10:19
Engr2012 wrote: ajayvyavahare wrote: If p,s, and t are positive integer, is pspt > p(st)
(1) p < s (2) s < t
need help to solve this one. Do not forget to mention the source of the question.it is simple after you realise that as p is positive, you can rewrite the given inequality as pspt > p(st) = pst > p(st) , you can also remove 'p' from both the sides , leaving you with is st > st which is very clearly obtainable if you know about the relative relation between t and s (side note, not required for this question: for st > st to be true, this means that st<0 or s<t)Statement 1, gives no information about relation between t and s , hence not sufficient. Statement 2, gives the exact relation we need to answer the question and as such is sufficient. B is the correct answer. Hope this helps. I did exactly what you did in this question but picked E. I was thinking x is x or x, so s  t can be equal to st or (st). Plugging in some numbers for s and t: 3  5= 2 and 3 + 5 = 2, so st could be equal to 2 or 2 which would be insufficient. Could you help me to understand why this is wrong? Tks



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Re: If p, s, and t are positive integer, is ps  pt > p(s  t) ? [#permalink]
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04 Jan 2017, 13:12
AJ1012 wrote: If p,s, and t are positive integer, is pspt > p(st)
(1) p < s (2) s < t
need help to solve this one. Excellent question, this one looks a lot tricker than it actually is. Took me for a ride until I saw the "only positive integers". So let's look at ps  pt > P(st) or rewrite it as  p(st) > p (st). Now let's consider a possibility where P(st) is greater than  p(st) , think about this one. I can't come up with one. So there's no way  p(st  < p (st). We know that p(st) is always positive. So if p (st) is negative then, lets call P (st) x, so x > x is equal when both positive and x < x when x is negative correct? Since all of them are positive, to make P (st) negative, T has to be bigger than S. That's the only option. No other way to make it negative since they're all positive. T > s is necessary. 1) insufficient. 2) sufficient ! Here's a easy way: rewrite : p (st) > p(st) let call inside X. x > x only if X is negative. so if all are positive, (st) has to be negative. for that T has to be bigger than S. Bam!
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Re: If p, s, and t are positive integer, is ps  pt > p(s  t) ? [#permalink]
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06 Jan 2017, 09:30
in the problem we can take p as common as: p(st) > p(st) so now we need to look at the values of s and t and which tells only statement 2 so its suff. to get a exact yes. hence answer is B



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Re: If p, s, and t are positive integer, is ps  pt > p(s  t) ? [#permalink]
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14 Aug 2017, 00:51
hi all, I still am unable to derive the relationship between the st > st. Can anyone please share an easier way to crack this. Thanks.
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Re: If p, s, and t are positive integer, is ps  pt > p(s  t) ? [#permalink]
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22 Sep 2017, 05:21
If p,s, and t are positive integer, is pspt > p(st) => Find is p(st) > p(st)
As we know x > x only when x is ve . When x is positive x =x
So here we have to check if product p*(st) is ve or not. => either p is ve or (st) is ve. If both ve, than product will become +ve => x=x
given in question stem that all variables are +ve. So we have to find if (st) is ve or not. => we have to find is s<t or not.
(1) p < s This just tell value of p is less than s . Not sufficient.
(2) s < t This directly gives us equation that we are looking for. => s<t => (st) is ve => p(st) is ve => p(st) > p(st) Sufficient
Answer: B



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Re: If p, s, and t are positive integer, is ps  pt > p(s  t) ? [#permalink]
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22 Sep 2017, 17:38
AnubhavK wrote: hi all, I still am unable to derive the relationship between the st > st. Can anyone please share an easier way to crack this. Thanks. Modulus is always positive or 0.Hence st will always be positive or 0. In this problem it can be zero since s can be equal to t (there is nothing that says that these numbers are unique) On the other hand, st will be positive if s>t and negative otherwise. Statement 2 clearly tells us that s<t. This means that the RHS will be negative. Since LHS, i.e Modulus of any value is always positive, we can answer this question using statement B alone.
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Re: If p, s, and t are positive integer, is ps  pt > p(s  t) ? [#permalink]
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15 Mar 2018, 14:41
AJ1012 wrote: If p,s, and t are positive integer, is pspt > p(st)
(1) p < s (2) s < t
need help to solve this one. so we have : p(st)>p(st) Now for L.H.S to be greater than R.H.S, 'p' and '(st)' should be of opposite signs (as L.H.S is in mod and will eventually become +ve because of mod) Thus, for 'p' and '(st)' to be of opposite signs , 'p' needs to be +ve and (st) needs to be ve.(p can't be negative as the question says p,s and t are +ve integers) Now: from 1) p<s>we get nothing...thus insufficient. from 2) s<t ===> (st)<0 . (as s,t are postive integers) thus sufficient . Answer B.
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Re: If p, s, and t are positive integer, is ps  pt > p(s  t) ? [#permalink]
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04 Apr 2018, 08:23
ENGRTOMBA2018 wrote: ajayvyavahare wrote: If p,s, and t are positive integer, is pspt > p(st)
(1) p < s (2) s < t
need help to solve this one. Do not forget to mention the source of the question.it is simple after you realise that as p is positive, you can rewrite the given inequality as pspt > p(st) = pst> p(st) , you can also remove 'p' from both the sides , leaving you with is st > st which is very clearly obtainable if you know about the relative relation between t and s (side note, not required for this question: for st > st to be true, this means that st<0 or s<t)Statement 1, gives no information about relation between t and s , hence not sufficient. Statement 2, gives the exact relation we need to answer the question and as such is sufficient. B is the correct answer. Hope this helps. Though this is a old post i think there is an error here pspt can't be written as pst (as i have highlighted above) but instead pspt = l P(st) l members plz correct me if i am wrong here



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Re: If p, s, and t are positive integer, is ps  pt > p(s  t) ? [#permalink]
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04 Apr 2018, 09:12
cruiseav wrote: ENGRTOMBA2018 wrote: ajayvyavahare wrote: If p,s, and t are positive integer, is pspt > p(st)
(1) p < s (2) s < t
need help to solve this one. Do not forget to mention the source of the question.it is simple after you realise that as p is positive, you can rewrite the given inequality as pspt > p(st) = pst> p(st) , you can also remove 'p' from both the sides , leaving you with is st > st which is very clearly obtainable if you know about the relative relation between t and s (side note, not required for this question: for st > st to be true, this means that st<0 or s<t)Statement 1, gives no information about relation between t and s , hence not sufficient. Statement 2, gives the exact relation we need to answer the question and as such is sufficient. B is the correct answer. Hope this helps. Though this is a old post i think there is an error here pspt can't be written as pst (as i have highlighted above) but instead pspt = l P(st) l members plz correct me if i am wrong here Hi cruiseavNote, here p,s & t are positive. so p can be moved out of modulus function and we can divide both sides of the inequality by p as this will not impact the inequality.




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