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Re: In a certain business, production index p is directly proportional to
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24 Aug 2018, 09:03
Bunuel wrote: gettinit wrote: Would p be directly proportional to i as well if e is proportional to p? I am thinking it should be, however the constant proportion will be different between p and e and e and i and thus entirely separate between p and i? thanks. \(a\) is directly proportional to \(b\) means that as the absolute value of \(b\) gets bigger, the absolute value of \(a\) gets bigger too, so there is some nonzero constant \(x\) such that \(a=xb\); So if \(a\) is directly proportional to \(b\) (\(a=xb\)), then viseversa is also correct: \(b\) is directly proportional to \(a\) (\(b=\frac{1}{x}*a\) as the absolute value of \(a\) gets bigger, the absolute value of \(b\) gets bigger too). \(a\) is inversely proportional to \(b\) means that as the absolute value of \(b\) gets bigger, the absolute value of \(a\) gets smaller, so there is some nonzero constant constant \(y\) such that \(a=\frac{y}{b}\).So if \(a\) is inversely proportional to \(b\) (\(a=\frac{y}{b}\)), then viseversa is also correct: \(b\) is inversely proportional to \(a\) (\(b=\frac{y}{a}\) as the absolute value of \(a\) gets bigger, the absolute value of \(b\) gets smaller). As for the question: In a certain business, production index p is directly proportional to efficiency index e, which is in turn directly proportional to investment i. What is p if i = 70?Given: \(p=ex\) and \(e=iy\) (for some constants \(x\) and \(y\)), so \(p=ixy\). Question: \(p=70xy=?\) So, basically we should find the value of \(xy\). (1) e = 0.5 whenever i = 60 > as \(e=iy\) then \(0.5=60y\) > we can find the value of \(y\), but still not sufficient. (2) p = 2.0 whenever i = 50 > as \(p=ixy\) then \(2=50xy\) > we can find the value of \(xy\). Sufficient. Answer: B. Hope it's clear. 2 = 50 x = 70 Cross Multiply x = 2.8 is it correct approach ? if not why ?



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Re: In a certain business, production index p is directly proportional to
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24 Aug 2018, 09:37
VeritasKarishma , Bunuel  is below approach correct ? What is p if i = 70? (1) e = 0.5 whenever i = 60 > no P , n no relation between e & P is established, hence insufficient (2) p = 2.0 whenever i = 50 (2) if i = 10 > P = 2/10 if i = 70 > P = 2/10 *7 > p=2.8



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In a certain business, production index p is directly proportional to
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24 Aug 2018, 09:40
VeritasKarishma , Bunuel  is below approach correct ? What is p if i = 70? (1) e = 0.5 whenever i = 60 > no P , n no relation between e & P is established, hence insufficient (2) p = 2.0 whenever i = 50 (2) if i = 10 > P = 2/10 if i = 70 > P = 2/10 *7 > p=2.8



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Re: In a certain business, production index p is directly proportional to
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25 Aug 2018, 06:18
s8kadian wrote: VeritasKarishma , Bunuel  is below approach correct ? What is p if i = 70? (1) e = 0.5 whenever i = 60 > no P , n no relation between e & P is established, hence insufficient (2) p = 2.0 whenever i = 50 (2) if i = 10 > P = 2/10 if i = 70 > P = 2/10 *7 > p=2.8 Yes it is fine but you first need to deduce that p is directly proportional to i to solve it this way.
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Re: In a certain business, production index p is directly proportional to
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06 Nov 2018, 19:21
I agree with this solution, and that is how i interpret Joint variations, However according to the Joint variations article If x is proportional to y and y is proportional z, then x is inversely proportional to z x/y=k y/z=k
Shouldnt x/yz =constant and not
xz/y = constant
The article says otherwise. I cannot tell the difference



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Re: In a certain business, production index p is directly proportional to
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21 Aug 2019, 04:21
Superhuman wrote: In a certain business, production index p is directly proportional to efficiency index e, which is in turn directly proportional to investment i. What is p if i = 70?
(1) e = 0.5 whenever i = 60 (2) p = 2.0 whenever i = 50 Given: In a certain business, production index p is directly proportional to efficiency index e, which is in turn directly proportional to investment i. Asked: What is p if i = 70? p = k1 * e e = k2 * i p = k1 * k2 * i = k * i where k = k1 * k2 p = 70 k = 70 k1 * k2 if i = 70 (1) e = 0.5 whenever i = 60 e = k2 * i .5 = k2 * 60 k2 = .5/60 = 1/120 Since k1 is unknown NOT SUFFICIENT (2) p = 2.0 whenever i = 50 p = k* i 2 = k * 50 k = 2/ 50 = 1/25 p = 70 k = 70 /25 = 2.8 SUFFICIENT IMO B



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Re: In a certain business, production index p is directly proportional to
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21 Aug 2019, 04:23
vishaldd01 wrote: I agree with this solution, and that is how i interpret Joint variations, However according to the Joint variations article If x is proportional to y and y is proportional z, then x is inversely proportional to z x/y=k y/z=k
Shouldnt x/yz =constant and not
xz/y = constant
The article says otherwise. I cannot tell the difference vishaldd01 Please see my solution.



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Re: In a certain business, production index p is directly proportional to
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21 Aug 2019, 04:24
VeritasKarishma wrote: s8kadian wrote: VeritasKarishma , Bunuel  is below approach correct ? What is p if i = 70? (1) e = 0.5 whenever i = 60 > no P , n no relation between e & P is established, hence insufficient (2) p = 2.0 whenever i = 50 (2) if i = 10 > P = 2/10 if i = 70 > P = 2/10 *7 > p=2.8 Yes it is fine but you first need to deduce that p is directly proportional to i to solve it this way. s8kadian see how p is directly proportional to i in my solution




Re: In a certain business, production index p is directly proportional to
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21 Aug 2019, 04:24



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