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Which of the following statements is true? [#permalink]
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27 Aug 2010, 07:15
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Which of the following statements is true? A. \(3\sqrt{7}<2\sqrt{15}<\frac{5\sqrt{13}}{sqrt{5}}<\frac{39}{5}\) B. \(2\sqrt{15}<\frac{39}{5}<3\sqrt{7}<\frac{5\sqrt{13}}{sqrt{5}}\) C. \(2\sqrt{15}<3\sqrt{7}<\frac{39}{5}<\frac{5\sqrt{13}}{sqrt{5}}\) D. \(2\sqrt{15}<3\sqrt{7}<\frac{5\sqrt{13}}{sqrt{5}}<\frac{39}{5}\) E. \(2\sqrt{15}<\frac{5\sqrt{13}}{sqrt{5}}<3\sqrt{7}<\frac{39}{5}\)
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Re: Which of the following statements is true? [#permalink]
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27 Aug 2010, 08:06
Answer should be C Make all the Fraction with same denominator that way it would be much easier as only one option lefts.....!!!!
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Re: Which of the following statements is true? [#permalink]
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14 Sep 2010, 04:18
any quick way to solve this plsss...???



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Re: Which of the following statements is true? [#permalink]
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14 Sep 2010, 09:54
utin wrote: any quick way to solve this plsss...??? hi, By observing carefully we can see that all answer choice compare 4 different value types of which 3 are in some form of sqrt...... well for a question like this strategy should be to take all the value inside square root and then compare each.. 39/5 will be approx 8 which will be sqrt of 64 and then u can compare all the values easily....... hope it helps u thanx



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Re: Which of the following statements is true? [#permalink]
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14 Sep 2010, 11:50
sandeep800 wrote: utin wrote: any quick way to solve this plsss...??? hi, By observing carefully we can see that all answer choice compare 4 different value types of which 3 are in some form of sqrt...... well for a question like this strategy should be to take all the value inside square root and then compare each.. 39/5 will be approx 8 which will be sqrt of 64 and then u can compare all the values easily....... hope it helps u thanx Nice idea. I was going decimal route which will be bad.
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Re: Which of the following statements is true? [#permalink]
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14 Sep 2010, 11:56
saxenashobhit wrote: sandeep800 wrote: utin wrote: any quick way to solve this plsss...??? hi, By observing carefully we can see that all answer choice compare 4 different value types of which 3 are in some form of sqrt...... well for a question like this strategy should be to take all the value inside square root and then compare each.. 39/5 will be approx 8 which will be sqrt of 64 and then u can compare all the values easily....... hope it helps u thanx Nice idea. I was going decimal route which will be bad. Thanx shobhit..sometime pattern of answer choices gives us the way to solve!!!



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Re: Which of the following statements is true? [#permalink]
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14 Sep 2010, 18:30
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B. you have to be careful while doing such approximations.
If you bring everything under a squareroot it becomes obvious.
so it becomes sqrt(63), sqrt(60), sqrt(65), [39/5=sqrt(7.8*7.8) = sqrt(60.84)]
You should be careful while thinking of 7.8 as 8... just watch out ...coz in this case if you would get B as the answer. Not C.



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Re: Which of the following statements is true? [#permalink]
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14 Sep 2010, 20:23
hemanthp wrote: B. you have to be careful while doing such approximations.
If you bring everything under a squareroot it becomes obvious.
so it becomes sqrt(63), sqrt(60), sqrt(65), [39/5=sqrt(7.8*7.8) = sqrt(60.84)]
You should be careful while thinking of 7.8 as 8... just watch out ...coz in this case if you would get B as the answer. Not C. Thanx hemanth for pointing out that!!i actually dint solved the question..was just trying to tell the strategy we can use here....



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Re: Which of the following statements is true? [#permalink]
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15 Sep 2010, 08:40
hemanthp wrote: B. you have to be careful while doing such approximations.
If you bring everything under a squareroot it becomes obvious.
so it becomes sqrt(63), sqrt(60), sqrt(65), [39/5=sqrt(7.8*7.8) = sqrt(60.84)]
You should be careful while thinking of 7.8 as 8... just watch out ...coz in this case if you would get B as the answer. Not C. This is where i was stuck. Thanks Hemanthp



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Re: Which of the following statements is true? [#permalink]
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25 Dec 2017, 03:34
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Squaring each term and then comparing makes life easy
\((3 \sqrt{7})^2\) = \(9 * 7\) = \(63\)
\((2 \sqrt{15})^2\) = \(4 * 15\) = \(60\)
\((39/5)^2\) = 1521/25 = \(60.x\) (some decimal)
\((5 \sqrt{13} / \sqrt{5})^2\) = \(25 * 13 / 5\) = \(65\)
60 < 60.x < 63 < 65
Answer (B)




Re: Which of the following statements is true?
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25 Dec 2017, 03:34






