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If a is an integer and a=b/b is a=1 [#permalink]
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18 Feb 2012, 05:04
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If a is an integer and a=b/b is a=1 (1) b> 0 (2) a>1
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Re: is a =1 [#permalink]
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18 Feb 2012, 05:16




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Re: If a is an integer and a=b/b is a=1 [#permalink]
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18 Feb 2012, 05:21
B thanks i thought non zero / 0 was undefined and 0 / 0 = 0 but if the former is undefined too then the question is missing the b <> 0 clause thanks
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Re: If a is an integer and a=b/b is a=1 [#permalink]
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18 Feb 2012, 05:27



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Re: is a =1 [#permalink]
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25 Feb 2012, 12:10
Bunuel wrote: If a is an integer and a=b/b is a=1
If it were a realistic GMAT question it would mention that b does not equal to zero (because b is in denominator and division by zero is undefined). So, the proper question should read:
If b does not equal tot zero and a=b/b is a=1
Now, if \(b>0\) then \(a=\frac{b}{b}=\frac{b}{b}=1\) and if \(b<0\) then \(a=\frac{b}{b}=\frac{b}{b}=1\). So, the question basically asks whether we have the first case.
(1) b>0. Sufficient. (2) a>1. Since \(a\) can take only 2 values 1 and 1 and this statement tells that \(a\) is not 1 then \(a=1\). Sufficient.
Answer: D.
Hope it's clear. Bunuel, For this statement. if \(b<0\) then \(a=\frac{b}{b}=\frac{b}{b}=1\). If b < 0, b = b. Would not you consider b = b so that result of division is 1 [ b / b ]. I understand that this does not change the answer anyways but just wanted to know. Regards



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Re: is a =1 [#permalink]
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25 Feb 2012, 12:20
saxenaashi wrote: Bunuel wrote: If a is an integer and a=b/b is a=1
If it were a realistic GMAT question it would mention that b does not equal to zero (because b is in denominator and division by zero is undefined). So, the proper question should read:
If b does not equal tot zero and a=b/b is a=1
Now, if \(b>0\) then \(a=\frac{b}{b}=\frac{b}{b}=1\) and if \(b<0\) then \(a=\frac{b}{b}=\frac{b}{b}=1\). So, the question basically asks whether we have the first case.
(1) b>0. Sufficient. (2) a>1. Since \(a\) can take only 2 values 1 and 1 and this statement tells that \(a\) is not 1 then \(a=1\). Sufficient.
Answer: D.
Hope it's clear. Bunuel, For this statement. if \(b<0\) then \(a=\frac{b}{b}=\frac{b}{b}=1\). If b < 0, b = b. Would not you consider b = b so that result of division is 1[ b / b ]. I understand that this does not change the answer anyways but just wanted to know. Regards First of all: if \(b<0\) then \(a=\frac{b}{b}=\frac{b}{b}=1\). You can not say "let's consider that b=b", since you have what you have: \(\frac{b}{b}\) which equals to 1 only. Next, if \(b=b\) then \(2b=0\) and \(b=0\), which is not possible, since \(b\) is in the denominator. Hope it's clear.
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Re: is a =1 [#permalink]
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25 Feb 2012, 12:34
Bunuel wrote: saxenaashi wrote: Bunuel wrote: If a is an integer and a=b/b is a=1
If it were a realistic GMAT question it would mention that b does not equal to zero (because b is in denominator and division by zero is undefined). So, the proper question should read:
If b does not equal tot zero and a=b/b is a=1
Now, if \(b>0\) then \(a=\frac{b}{b}=\frac{b}{b}=1\) and if \(b<0\) then \(a=\frac{b}{b}=\frac{b}{b}=1\). So, the question basically asks whether we have the first case.
(1) b>0. Sufficient. (2) a>1. Since \(a\) can take only 2 values 1 and 1 and this statement tells that \(a\) is not 1 then \(a=1\). Sufficient.
Answer: D.
Hope it's clear. Bunuel, For this statement. if \(b<0\) then \(a=\frac{b}{b}=\frac{b}{b}=1\). If b < 0, b = b. Would not you consider b = b so that result of division is 1[ b / b ]. I understand that this does not change the answer anyways but just wanted to know. Regards First of all: if \(b<0\) then \(a=\frac{b}{b}=\frac{b}{b}=1\). You can not say "let's consider that b=b", since you have what you have: \(\frac{b}{b}\) which equals to 1 only. Next, if \(b=b\) then \(2b=0\) and \(b=0\), which is not possible, since \(b\) is in the denominator. Hope it's clear. I guess I framed my question incorrectly. Let me try again. When we consider b < 0, would not the denominator be negative as well. b is b for b < 0. Consider b = 2. So a = b / b > 2 / 2 = 1



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Re: is a =1 [#permalink]
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25 Feb 2012, 12:47
saxenaashi wrote: I guess I framed my question incorrectly. Let me try again.
When we consider b < 0, would not the denominator be negative as well. b is b for b < 0. Consider b = 2. So a = b / b > 2 / 2 = 1 Again, irrespective of the question: \(\frac{b}{b}=1\) ONLY: \(\frac{b}{b}=(\frac{b}{b})=1\). Next, as for you reasoning: if \(b<0\), so when \(b\) is negative then \(b=negative=positive\), so denominator will be negative as it's \(b\), but nominator \({b}\) will be positive. So, if \(b=2<0\): \(\frac{2}{2}=\frac{2}{2}=1\). Remember b is an absolute value of b and it's always nonegative.
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Re: If a is an integer and a=b/b is a=1 [#permalink]
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26 Feb 2012, 06:12
rxs0005 wrote: If a is an integer and a=b/b is a=1
(1) b> 0 (2) a>1 The answer is "D" a = IbI/b = (+/)*b/b = (+/)*1 ........(i) If b > 0, then IbI/b >0 ==> a = 1 hence (1) is sufficient if a > 1 , then a = 1 from eq (i). hence (2) is also sufficient Hence D



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Re: If a is an integer and a=b/b is a=1 [#permalink]
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03 Jul 2015, 10:41
Bunuel wrote: If a is an integer and a=b/b is a=1
If it were a realistic GMAT question it would mention that b does not equal to zero (because b is in denominator and division by zero is undefined). So, the proper question should read:
If b does not equal tot zero and a=b/b is a=1
Now, if \(b>0\) then \(a=\frac{b}{b}=\frac{b}{b}=1\) and if \(b<0\) then \(a=\frac{b}{b}=\frac{b}{b}=1\). So, the question basically asks whether we have the first case.
(1) b>0. Sufficient. (2) a>1. Since \(a\) can take only 2 values 1 and 1 and this statement tells that \(a\) is not 1 then \(a=1\). Sufficient.
Answer: D.
Hope it's clear. Bunuel: The question states a is an integer. Hence b cannot be zero or else the equation wont hold. Therefore a has to be 1 from usage of either statement



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Re: If a is an integer and a=b/b is a=1 [#permalink]
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22 Jul 2015, 15:44
Bunuel wrote: If a is an integer and a=b/b is a=1
If it were a realistic GMAT question it would mention that b does not equal to zero (because b is in denominator and division by zero is undefined). So, the proper question should read:
If b does not equal tot zero and a=b/b is a=1
Now, if \(b>0\) then \(a=\frac{b}{b}=\frac{b}{b}=1\) and if \(b<0\) then \(a=\frac{b}{b}=\frac{b}{b}=1\). So, the question basically asks whether we have the first case.
(1) b>0. Sufficient. (2) a>1. Since \(a\) can take only 2 values 1 and 1 and this statement tells that \(a\) is not 1 then \(a=1\). Sufficient.
Answer: D.
Hope it's clear. Thanks for the clarification. I considered the 0case and realized A as the answer. I was pretty surprised at the OA



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Re: If a is an integer and a=b/b is a=1 [#permalink]
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27 Oct 2016, 15:13
It is not very clear to me that why b can't be 0. Question stem just has an expression a = b/b. a will be defined only when b is nonzero. How can we assume b is nonzero?



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Re: If a is an integer and a=b/b is a=1 [#permalink]
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22 Sep 2017, 00:14
1) b>0. Sufficient. (2) a>1. Since aa can take only 2 values 1 and 1 and this statement tells that aa is not 1 then a=1a=1. Sufficient.
Answer: D.



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Re: If a is an integer and a=b/b is a=1 [#permalink]
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27 Nov 2017, 00:08
manhasnoname wrote: It is not very clear to me that why b can't be 0. Question stem just has an expression a = b/b. a will be defined only when b is nonzero. How can we assume b is nonzero? Hi Just as you said, a will be defined only when b is nonzero. So b cannot be zero here, we can safely assume that.




Re: If a is an integer and a=b/b is a=1
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