SQ root

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SQ root

by JeetGulia » Wed Jul 21, 2010 1:20 pm
If sq. root of n is a positive integer, what is the value of n?
(1) 1 <sr.root of n <5
(2) l0 < n < 24

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by clock60 » Wed Jul 21, 2010 2:10 pm
got E here
(1) n can be 4,9,16 ,as sq root 4=2, 1<2<5. sq root 9=3. 1<3<5 the value of n is not fixed here so insuffiicent
(2) i did`t get from the 2 st
is it 10<n<25, or 0<n<24
in case that it is
0<n<24, n can be 1, 4,9,16, insufficient
if it 10<n<24 then n=16 sufficient
so need to clarify

(by the way we are given the sq root of n is +ve integer, i wonder how it can be -ve)

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by Patrick_GMATFix » Wed Jul 21, 2010 2:47 pm
JeetGulia wrote:(2) l0 < n < 24
Hey Jeet, I have trouble reading this statement. does it say 10? or 0? Because that will change the answer
clock60 wrote:(by the way we are given the sq root of n is +ve integer, i wonder how it can be -ve)
Hey Clock. The information "sq root of n is a positive integer" is still helpful because most square roots are not integers. This guarantees that n is a perfect square, not just any positive value.

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by JeetGulia » Wed Jul 21, 2010 2:50 pm
clock60 wrote:got E here
(1) n can be 4,9,16 ,as sq root 4=2, 1<2<5. sq root 9=3. 1<3<5 the value of n is not fixed here so insuffiicent
(2) i did`t get from the 2 st
is it 10<n<25, or 0<n<24
in case that it is
0<n<24, n can be 1, 4,9,16, insufficient
if it 10<n<24 then n=16 sufficient
so need to clarify

(by the way we are given the sq root of n is +ve integer, i wonder how it can be -ve)
..Nope answer is D..
1) I don't know how come it is sufficient.
2) would be 16...and square root would be 4.

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by JeetGulia » Wed Jul 21, 2010 2:51 pm
Patrick_GMATFix wrote:
JeetGulia wrote:(2) l0 < n < 24
Hey Jeet, I have trouble reading this statement. does it say 10? or 0? Because that will change the answer
clock60 wrote:(by the way we are given the sq root of n is +ve integer, i wonder how it can be -ve)
Hey Clock. The information "sq root of n is a positive integer" is still helpful because most square roots are not integers. This guarantees that n is a perfect square, not just any positive value.

-Patrick
It is 10

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by Patrick_GMATFix » Wed Jul 21, 2010 3:45 pm
JeetGulia wrote:If sq. root of n is a positive integer, what is the value of n?
(1) 1 <sr.root of n <5
(2) 10 < n < 24
root(n) = int >> n = int^2. so n is a perfect square. n = {1, 4, 9, 16, 25...}. The first statement doesn't limit us to a unique value because root(n) could be {2, 3, or 4} and each value would give us a different n. Statement 2 is sufficient because the only possible value of n that fits this range is n=16.

Pick B. To create drills with similar questions, set topic='Number Properties and Exponents & Roots' and difficulty='200-400 & 400-500' in the Drill Generator

Good luck
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by clock60 » Wed Jul 21, 2010 10:09 pm
Patrick_GMATFix wrote:
JeetGulia wrote:(2) l0 < n < 24
Hey Jeet, I have trouble reading this statement. does it say 10? or 0? Because that will change the answer
clock60 wrote:(by the way we are given the sq root of n is +ve integer, i wonder how it can be -ve)
Hey Clock. The information "sq root of n is a positive integer" is still helpful because most square roots are not integers. This guarantees that n is a perfect square, not just any positive value.

-Patrick
hi Patrick
i readily admit that n can be non integer, in my question i wonder how the square root can be negative

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by selango » Thu Jul 22, 2010 2:04 am
Square root of a positive integer can have positive and negative integer.

For ex sqrt(16)= 4 or -4

In this question what they r mentioning s that n is a perfect square and its root is positive.
--Anand--