If x and y are integers and y = |x + 3| + |4 - x|, does y equal 7?
(1) x < 4
(2) x > -3
OA C
Regards,
Uva.
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If x and y are integers
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Hi Uva@90,
This question can be solved by TESTing VALUES.
We're told that X and Y are INTEGERS and that Y = |X+3| + |4 - X|. We're asked if Y equals 7. This is a YES/NO question.
Fact 1: X < 4
IF...
X = 3
Y = |3+3| + |4-3| = 7 and the answer to the question is YES
IF...
X = -10
Y = |-10+3| + |4-(-10)| = 21 and the answer to the question is NO
Fact 1 is INSUFFICIENT
Fact 2: X > -3
IF...
X = 3
Y = |3+3| + |4-3| = 7 and the answer to the question is YES
IF...
X = 10
Y = |10+3| + |4-10| = 19 and the answer to the question is NO
Fact 2 is INSUFFICIENT
Combined, we know...
-3 < X < 4
Since X is an INTEGER, there are a limited possible number of values for X: -2, -1, 0, 1, 2, and 3. If you TEST each of these values, you'll find that the resulting sum is ALWAYS 7. It'll take a bit of work, but the work is easy.
Combined, SUFFICIENT
Final Answer: C
GMAT assassins aren't born, they're made,
Rich
This question can be solved by TESTing VALUES.
We're told that X and Y are INTEGERS and that Y = |X+3| + |4 - X|. We're asked if Y equals 7. This is a YES/NO question.
Fact 1: X < 4
IF...
X = 3
Y = |3+3| + |4-3| = 7 and the answer to the question is YES
IF...
X = -10
Y = |-10+3| + |4-(-10)| = 21 and the answer to the question is NO
Fact 1 is INSUFFICIENT
Fact 2: X > -3
IF...
X = 3
Y = |3+3| + |4-3| = 7 and the answer to the question is YES
IF...
X = 10
Y = |10+3| + |4-10| = 19 and the answer to the question is NO
Fact 2 is INSUFFICIENT
Combined, we know...
-3 < X < 4
Since X is an INTEGER, there are a limited possible number of values for X: -2, -1, 0, 1, 2, and 3. If you TEST each of these values, you'll find that the resulting sum is ALWAYS 7. It'll take a bit of work, but the work is easy.
Combined, SUFFICIENT
Final Answer: C
GMAT assassins aren't born, they're made,
Rich
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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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