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PR- Unable to match the answer given

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PR- Unable to match the answer given

by Xia_devil » Tue Jun 24, 2008 2:55 am
How many perfect squares are less than the integer d?

(1) 23 < d < 33
(2) 27 < d < 37


Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient.

Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient.

BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is sufficient.

EACH statement ALONE is sufficient.

Statements (1) and (2) TOGETHER are NOT SUFFICIENT


I though C was the right answer.. but.. not to be so.. could you help.. ?
With regards,
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by atlantic » Tue Jun 24, 2008 3:12 am
Answer A.

Pls remind that 'd' is an integer.

(1) let d=26, 26<33 and since 25 is less than 26 (as requested by the question) and is greater than 23, we have one perfect square. SUFF

(2) let d=36, 36<37 but any integer less than 36 must be any number lower than 35 but no smaller than 28, and in this serie you cannot find one single perfect square INSUFF.

Hope it helps.
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by Amitk101 » Tue Jun 24, 2008 11:58 pm
I think the answer should be "B".

Reason:

perfect square are 4,9,16,25,36.

consider A) d can have a value of 24 or 27, which will change the number of perfect square which are less than d. NOT SUFF

consider B) if d=28, number of square below it is 4. If d=36 then also its 4.

Any thoughts?
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by Ian Stewart » Wed Jun 25, 2008 5:05 am
Amitk101 wrote:I think the answer should be "B".

Reason:

perfect square are 4,9,16,25,36.
Yes, B should be the answer, and for the reasons you mention. I just wanted to correct one small (and very common) omission in the above. A number is a perfect square if it is the square of an integer. The smallest perfect square is not 4; it's 0, because 0^2 = 0. And 1^2 = 1, so 1 is another perfect square.
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Bit tricky answer B

by nareshchellani » Wed Jun 25, 2008 5:28 am
26<d<37 do d max 36, but perfect sq less then 36, so 36 is not included.
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hu?

by augusto » Sat Jul 26, 2008 9:07 am
Hi guys,

Could anyone explain me better the question? I know what a perfect square is, but I don't I understand the question itself.

How many perfect squares are less than the integer d?

What I know is that between 23 < d < 33 the only perfect square is 5 and between 27 < d < 37 the only perfect square is 36.


Thanks a lot,
Augusto
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Could anyone explain me better the question?

by Has » Sat Jul 26, 2008 1:06 pm
Augesto

the q is asking for how many perfect squares less the integer d, so all those that are below it (the integer d).

with A, the integer d can be above or below 25, which will make a difference to how many perfect squares (listed above) there are,

with B, the number must be higher then 25 (above 27), yet only up to 36, thus if d is any of the available numbers in this option (even perfect square 36), the perfect squares BELOW it, i.e. less then it are the same - 36 will not be included as it is not less then itself

Therefore, only B is sufficent to answer the q

hope this clarifies

H
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by augusto » Sat Jul 26, 2008 11:41 pm
Thanks!
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by kris610 » Sun Jul 27, 2008 3:22 pm
I agree with B:

Given a range like this, take the extreme cases: Min 28 and Max 36. For either of them, you'll get the same result.
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by microke » Mon Jul 28, 2008 1:08 am
what is the OA? Can the originator reveal?
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