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\(a^2*(b+3)*(c+9)=1\), where a, b and c are integers. Find the value of b*c?

Now \(a^2*(b+3)*(c+9)=1\) will be TRUE only when the terms in product are -1 or 1..
So b+3=1...b=-2, and c+9=1...c=-8...b*c=(-2)*(-8)=16
OR b+3=-1...b=-4, and c+9=-1...c=-10...b*c=(-4)(-10)=40

1) b*c>16
So, b*c=40
Suff

2) b*c is square of positive number.
If the intention is to say that \(\sqrt{40}\) is also positive number, it would be better to say that b*c is a square.
You will never find such wordings in GMAT.

b*c=16 as 40 is NOT a square.
Suff

D..

But the problem is that BOTH statements contradict each other ???
So a faulty question.
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Read the second statement again.
It says square of positive number, not integer.

B is clearly not sufficient. I guess you got trapped. FYI i have seen such language in plenty of questions.

chetan2u
\(a^2*(b+3)*(c+9)=1\), where a, b and c are integers. Find the value of b*c?

Now \(a^2*(b+3)*(c+9)=1\) will be TRUE only when the terms in product are -1 or 1..
So b+3=1...b=-2, and c+9=1...c=-8...b*c=(-2)*(-8)=16
OR b+3=-1...b=-4, and c+9=-1...c=-10...b*c=(-4)(-10)=40

1) b*c>16
So, b*c=40
Suff

2) b*c is square of positive number.
If the intention is to say that \(\sqrt{40}\) is also positive number, it would be better to say that b*c is a square.
You will never find such wordings in GMAT.

b*c=16 as 40 is NOT a square.
Suff

D..

But the problem is that BOTH statements contradict each other ???
So a faulty question.
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nick1816
Read the second statement again.
It says square of positive number, not integer.

B is clearly not sufficient. I guess you got trapped.

chetan2u
\(a^2*(b+3)*(c+9)=1\), where a, b and c are integers. Find the value of b*c?

Now \(a^2*(b+3)*(c+9)=1\) will be TRUE only when the terms in product are -1 or 1..
So b+3=1...b=-2, and c+9=1...c=-8...b*c=(-2)*(-8)=16
OR b+3=-1...b=-4, and c+9=-1...c=-10...b*c=(-4)(-10)=40

1) b*c>16
So, b*c=40
Suff

2) b*c is square of positive number.
If the intention is to say that \(\sqrt{40}\) is also positive number, it would be better to say that b*c is a square.
You will never find such wordings in GMAT.

b*c=16 as 40 is NOT a square.
Suff

D..

But the problem is that BOTH statements contradict each other ???
So a faulty question.


Hi,

I did not get trapped. I have written in RED in explanation that if your intention is to say that \(\sqrt{40}\) is also positive number, the words chosen are poor. You will never find a statement like that.
A very poor quality question as also tagged the same by Bunuel. I can bet it is NOT from any possible reliable source. Please share the source and give examples of same kind from reliable source if you have come across something like that.
2) b*c is square of positive number.
Language is poor. Also what exactly square of positive number means when b*c will remain the same even if it was square of negative number as square is positive always.

You may as well just dump the source, which does not follow the language of GMAT.
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I can't dump my mind tho. It's a self-made question.
There are plenty of official questions in which positive numbers are used for rational, irrational numbers. IMO this question is perfectly alright ( it doesn't matter if Bunuel tagged it poor quality or not.)

chetan2u
nick1816
Read the second statement again.
It says square of positive number, not integer.

B is clearly not sufficient. I guess you got trapped.

chetan2u
\(a^2*(b+3)*(c+9)=1\), where a, b and c are integers. Find the value of b*c?

Now \(a^2*(b+3)*(c+9)=1\) will be TRUE only when the terms in product are -1 or 1..
So b+3=1...b=-2, and c+9=1...c=-8...b*c=(-2)*(-8)=16
OR b+3=-1...b=-4, and c+9=-1...c=-10...b*c=(-4)(-10)=40

1) b*c>16
So, b*c=40
Suff

2) b*c is square of positive number.
If the intention is to say that \(\sqrt{40}\) is also positive number, it would be better to say that b*c is a square.
You will never find such wordings in GMAT.

b*c=16 as 40 is NOT a square.
Suff

D..

But the problem is that BOTH statements contradict each other ???
So a faulty question.


Hi,

I did not get trapped. I have written in RED in explanation that if your intention is to say that \(\sqrt{40}\) is also positive number, the words chosen are poor. You will never find a statement like that.
A very poor quality question as also tagged the same by Bunuel. I can bet it is NOT from any possible reliable source. You may as well just dump the source, which does not follow the language of GMAT.

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