Is the product abcd even?
1.a^2+b^2+c^2+d^2=0
2. a = b = c = d
[spoiler]OA: A[/spoiler]
but to me the answer is D
stat 2 is sufficient, bcuz it says all numbers are equal
if they r even product is even
if then are all odd, since all are equal it is like 4*X which will be even
what do u think?
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odd/even
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shankar.ashwin
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Statement 2:
a=b=c=d=1
a*b*c*d = 1 (odd) [abcd not equals 4a, a+a+a+a = 4a] think you mixed up the signs
a=b=c=d=1
a*b*c*d = 1 (odd) [abcd not equals 4a, a+a+a+a = 4a] think you mixed up the signs
mehrasa wrote:Is the product abcd even?
1.a^2+b^2+c^2+d^2=0
2. a = b = c = d
[spoiler]OA: A[/spoiler]
but to me the answer is D
stat 2 is sufficient, bcuz it says all numbers are equal
if they r even product is even
if then are all odd, since all are equal it is like 4*X which will be even
what do u think?
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rijul007
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If a=b=c=dmehrasa wrote:Is the product abcd even?
a = b = c = d
stat 2 is sufficient, bcuz it says all numbers are equal
if they r even product is even
if then are all odd, since all are equal it is like 4*X which will be even
what do u think?
a*b*c*d = a^4
We dont know if a is even or odd....
Hence this statement will be Insufficient
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GMATGuruNY
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Statement 1: a² + b² + c² + d² = 0.mehrasa wrote:Is the product abcd even?
1.a^2+b^2+c^2+d^2=0
2. a = b = c = d
[spoiler]OA: A[/spoiler]
but to me the answer is D
stat 2 is sufficient, bcuz it says all numbers are equal
if they r even product is even
if then are all odd, since all are equal it is like 4*X which will be even
what do u think?
Since the square of a number can never be negative, the only way to satisfy statement 1 is if a=b=c=d=0.
Thus, abcd = 0, which is even.
SUFFICIENT.
Statement 2: a=b=c=d.
If a=b=c=d=0, then abcd= 0*0*0*0 = 0, which is even.
If a=b=c=d=1, then abcd= 1*1*1*1 = 1, which is not even.
INSUFFICIENT.
The correct answer is A.
The following statement is incorrect:
a=b=c=d means that abcd = a*a*a*a = a�.if then are all odd, since all are equal it is like 4*X which will be even.
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Followed here and elsewhere by over 1900 test-takers.
I have worked with students based in the US, Australia, Taiwan, China, Tajikistan, Kuwait, Saudi Arabia -- a long list of countries.
My students have been admitted to HBS, CBS, Tuck, Yale, Stern, Fuqua -- a long list of top programs.
As a tutor, I don't simply teach you how I would approach problems.
I unlock the best way for YOU to solve problems.
For more information, please email me (Mitch Hunt) at [email protected].
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chieftang
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Amehrasa wrote:Is the product abcd even?
1.a^2+b^2+c^2+d^2=0
2. a = b = c = d
[spoiler]OA: A[/spoiler]
but to me the answer is D
stat 2 is sufficient, bcuz it says all numbers are equal
if they r even product is even
if then are all odd, since all are equal it is like 4*X which will be even
what do u think?
For case 2, 1*1*1*1 = odd.
