are u sure wordings are correct as minimum value for xy as per the norms given is -25 and max is 275
which are not in the option
what is the source
stuck on possible values of xy
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thephoenix
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Yes the wording is correct. I am having the same problem with the question you are. I do not get how the max is 300. It should be 275 (12 x 11). The source is the Princetom Review CAT. Below is the explanation they provide:
Yes. Calculate the upper and lower limits for the value of xy, -50 and 300, respectively. xy is less than, but can't be equal to, 300 because though x can equal 25, y is always less than 12. The same logic applies for the lower limit; xy must be greater than -50. The correct answer is E.
Yes. Calculate the upper and lower limits for the value of xy, -50 and 300, respectively. xy is less than, but can't be equal to, 300 because though x can equal 25, y is always less than 12. The same logic applies for the lower limit; xy must be greater than -50. The correct answer is E.
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eaakbari
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The answer is right, since there are no equality conditions in answer. If your answer was c or d there would be an argument.
Take an example
If x = -25 and y= -1.5
xy= -37.5
which is well within the -50 range but your answer would not be supported
Take an example
If x = -25 and y= -1.5
xy= -37.5
which is well within the -50 range but your answer would not be supported
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srinivasarajui
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I think this a question where we have find where the range finds best.
Let me show How i eliminated answer choices
Let x = -2 and Y =11 then xy = -22 Then a and b are eliminated.
To get XY value equal to -50 we need to have -2 * 25 which is not possible, Though x can 25 but y an not be -2. then c and d are eliminated.
So ans is E
Hope this will be usefully
Let me show How i eliminated answer choices
Let x = -2 and Y =11 then xy = -22 Then a and b are eliminated.
To get XY value equal to -50 we need to have -2 * 25 which is not possible, Though x can 25 but y an not be -2. then c and d are eliminated.
So ans is E
Hope this will be usefully
Srinu
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harshavardhanc
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the min value of XY will be -25 when X=25 and Y = -1 and which is greater than -50.LMK27 wrote:If x and y are integers, and -2 < x < 25 and -2 < y <12, what is the range of possible values for xy?
a) 4 < xy < 300
b) -2 < xy < 300
c) -50 < xy < 300
d) -50 < xy < 300
e) -50 < xy < 300
e
[spoiler][/spoiler]
the max will be 275 when X = 25 and Y = 11 and which is less than 300.
The only option showing this range is E.
Regards,
Harsha
Harsha
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Stuart@KaplanGMAT
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Since x and y are integers, the max value is indeed 25*11 = 275. Further, the min value is -1*25 = -25.LMK27 wrote:If x and y are integers, and -2 < x < 25 and -2 < y <12, what is the range of possible values for xy?
a) 4 < xy < 300
b) -2 < xy < 300
c) -50 < xy < 300
d) -50 < xy < 300
e) -50 < xy < 300
So, either the question is improperly constructed of there's a typo or two in the post. As written, C and D are just as valid as E.
The only way E is the correct answer is if x and y don't have to be integers.
Stuart Kovinsky | Kaplan GMAT Faculty | Toronto
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harshavardhanc
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Stuart Kovinsky wrote:Since x and y are integers, the max value is indeed 25*11 = 275. Further, the min value is -1*25 = -25.LMK27 wrote:If x and y are integers, and -2 < x < 25 and -2 < y <12, what is the range of possible values for xy?
a) 4 < xy < 300
b) -2 < xy < 300
c) -50 < xy < 300
d) -50 < xy < 300
e) -50 < xy < 300
So, either the question is improperly constructed of there's a typo or two in the post. As written, C and D are just as valid as E.
The only way E is the correct answer is if x and y don't have to be integers.
Stuart,
But C and D say that one of the possible values of XY can be -50, which I think is incorrect. Hence, IMO C and D do not show the range correctly.
Please correct me if I'm wrong.
Regards,
Harsha
Harsha
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Stuart@KaplanGMAT
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But E says that one of the possible values of XY is -49, which is also wrong; so, by the same reasoning, you should eliminate E.harshavardhanc wrote:
Stuart,
But C and D say that one of the possible values of XY can be -50, which I think is incorrect. Hence, IMO C and D do not show the range correctly.
Please correct me if I'm wrong.
So, either the question is:
"which of the following ranges includes all of the possible values of xy", in which case C, D and E are all correct; or
"which of the following is equivalent to all possible values of xy", in which case there's no correct answer.
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The question definitely has to be written wrong. When I was taking the test I thought it was me who was not understanding the question properly, so I am glad to see that it was the question that was wrong and not my logic.
Thanks everyone for your insight!
Thanks everyone for your insight!
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harshavardhanc
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Stuart,Stuart Kovinsky wrote:But E says that one of the possible values of XY is -49, which is also wrong; so, by the same reasoning, you should eliminate E.harshavardhanc wrote:
Stuart,
But C and D say that one of the possible values of XY can be -50, which I think is incorrect. Hence, IMO C and D do not show the range correctly.
Please correct me if I'm wrong.
So, either the question is:
"which of the following ranges includes all of the possible values of xy", in which case C, D and E are all correct; or
"which of the following is equivalent to all possible values of xy", in which case there's no correct answer.
Please help me understand this one.
E never says that XY can have a value of -49. It just says that the value of XY lies between -50 and 300 (both excluded), as there are only less than (<) signs in the option.
However, C and D explicitly say that XY lies between -50 and 300 and one of the possible value is -50, as there is less than or equal to sign in the option (<).
Am I wrong in my interpretation? Please help!
Last edited by harshavardhanc on Tue Apr 06, 2010 3:33 am, edited 1 time in total.
Regards,
Harsha
Harsha
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pradeepkaushal9518
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the answer E as x is from -1 to 24 and y is -1 to 11 so -24 is the lowest xy and 264 is highest so -50<xy<-300 is the correct answer
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Stuart@KaplanGMAT
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OK.. let's change the wording of C to better explain my point.harshavardhanc wrote: Stuart,
Please help me understand this one.
E never says that XY can have a value of -49. It just says that the value of XY lies between -50 and 300 (both excluded), as there are only less than (<) signs in the option.
However, C and D explicitly say that XY lies between -50 and 300 and one of the possible value is -50, as there is less than or equal to sign in the option (<).
Am I wrong in my interpretation? Please help!
If C had said:
-51 < xy < 301
then would it have been as equally correct as E?
Given that we know xy is an integer, my restatement of C has the exact same meaning as the original C; just because something has "greater than or equal to" doesn't imply more than "greater than" in terms of what the number actually is.
For example, if x=5, it's equally correct to say:
-10 < x < 100
and
-10 <= x <= 100
Remember, "<=" means "less than OR equal to" - it doesn't mean that it MUST be equal to that number.
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