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555-605 (Medium)|   Roots|      
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Bunuel
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Which of the following is equivalent to 21^(1/2)/6 ? 09 Feb 2017, 05:57
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C
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25% (medium)

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77% (01:23) correct 23% (01:42) wrong based on 537 sessions

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Which of the following is equivalent to \(\frac{\sqrt{21}}{6}\)?

A. \(\frac{\sqrt{7}}{2}\)

B. \(\sqrt{\frac{7}{2}}\)

C. \(\sqrt{\frac{7}{12}}\)

D. \(\frac{7}{\sqrt{6}}\)

E. \(\frac{21\sqrt{6}}{6}\)
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C
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JeffTargetTestPrep
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Which of the following is equivalent to 21^(1/2)/6 ? 13 Feb 2017, 17:07
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Bunuel
Which of the following is equivalent to \(\frac{\sqrt{21}}{6}\)?

A. \(\frac{\sqrt{7}}{2}\)

B. \(\sqrt{\frac{7}{2}}\)

C. \(\sqrt{\frac{7}{12}}\)

D. \(\frac{7}{\sqrt{6}}\)

E. \(\frac{21\sqrt{6}}{6}\)
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Let’s simplify the given expression:

√(21)/6 = √(21)/√(36) = √(21/36) = √(7/12)

Answer: C
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rohit8865
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Which of the following is equivalent to 21^(1/2)/6 ? 09 Feb 2017, 12:20
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Bunuel
Which of the following is equivalent to \(\frac{\sqrt{21}}{6}\)?

A. \(\frac{\sqrt{7}}{2}\)

B. \(\sqrt{\frac{7}{2}}\)

C. \(\sqrt{\frac{7}{12}}\)

D. \(\frac{7}{\sqrt{6}}\)

E. \(\frac{21\sqrt{6}}{6}\)
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multiply and divide by √21 to get 21/(6*√21)
or 7/2√21

or √49/√(4*21)

or √(49/84)

√7/12--------(dividing by 7)

Ans C
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Which of the following is equivalent to 21^(1/2)/6 ? 09 Feb 2017, 13:24
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√21/6, can be written as √21/(√4 * √9)

=> Cancelling out √3 from numerator and denominator, we get √7/(√4 * √3)

=> Above can be written as √7/√12

Therefore, Answer is C
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Which of the following is equivalent to 21^(1/2)/6 ? 12 Apr 2017, 07:39
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JeffTargetTestPrep
Bunuel
Which of the following is equivalent to \(\frac{\sqrt{21}}{6}\)?

A. \(\frac{\sqrt{7}}{2}\)

B. \(\sqrt{\frac{7}{2}}\)

C. \(\sqrt{\frac{7}{12}}\)

D. \(\frac{7}{\sqrt{6}}\)

E. \(\frac{21\sqrt{6}}{6}\)

Let’s simplify the given expression:

√(21)/6 = √(21)/√(36) = √(21/36) = √(7/12)

Answer: C
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why you took denominator in root any particular reason
TIA
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Which of the following is equivalent to 21^(1/2)/6 ? 12 Apr 2017, 08:05
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ehsan090
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Bunuel
Which of the following is equivalent to \(\frac{\sqrt{21}}{6}\)?

A. \(\frac{\sqrt{7}}{2}\)

B. \(\sqrt{\frac{7}{2}}\)

C. \(\sqrt{\frac{7}{12}}\)

D. \(\frac{7}{\sqrt{6}}\)

E. \(\frac{21\sqrt{6}}{6}\)

Let’s simplify the given expression:

√(21)/6 = √(21)/√(36) = √(21/36) = √(7/12)

Answer: C

why you took denominator in root any particular reason
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because you have to reduce the expresson
and we can reduce by cancelling factor 3 which is present in both num. & denominator :)
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Which of the following is equivalent to 21^(1/2)/6 ? 12 Apr 2017, 08:18
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Bunuel
Which of the following is equivalent to \(\frac{\sqrt{21}}{6}\)?

A. \(\frac{\sqrt{7}}{2}\)

B. \(\sqrt{\frac{7}{2}}\)

C. \(\sqrt{\frac{7}{12}}\)

D. \(\frac{7}{\sqrt{6}}\)

E. \(\frac{21\sqrt{6}}{6}\)
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Square both Numerator and Denominator : \(\frac{21}{36}\) => \(\frac{7}{12}\)

Since, we have taken square both in numerator and denominator, the actual value of the fraction will be : \(\sqrt{\frac{7}{12}}\)

Hence, answer must be (C) \(\sqrt{\frac{7}{12}}\)
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Which of the following is equivalent to 21^(1/2)/6 ? 13 Apr 2017, 00:47
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[/quote]

why you took denominator in root any particular reason
TIA[/quote]


because you have to reduce the expresson
and we can reduce by cancelling factor 3 which is present in both num. & denominator :)[/quote]

Thanks mate a little clear. I need to practice these type of question for more clear understanding
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Which of the following is equivalent to 21^(1/2)/6 ? 16 Dec 2017, 09:04
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√21/6
=√3*√7/3*2
=√7/√3*√4 as √4=2
=√7/√12
=√(7/12) Hence, Answer is C
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Which of the following is equivalent to 21^(1/2)/6 ? 26 Apr 2023, 18:34
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sqrt (21) / 6 is less than 1

The only option in the answer choices that is less than 1 is C.

Hope this helps
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Which of the following is equivalent to 21^(1/2)/6 ? 06 Nov 2025, 11:39
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