If x and y are positive, is 3x > 7y?
(1) x > y + 4
(2) -5x < -14y
Ans D????
IMO B
number properties
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i go with D as well...arorag wrote:If x and y are positive, is 3x > 7y?
(1) x > y + 4
(2) -5x < -14y
Ans D????
IMO B
statement 1,
take the minimum value of X and y
X should be 6 and y 1 ( i am taking integers for convenience sake... the Questions doesnt say anything abt integers)
6> 1+4
3X>7y
3.6 >7.1 yes.... sufficient.
statement 2.
-5x < -14y
X= 3 y = 1
-15< -14
3*3 > 7*1 hence sufficient..
hence D.
hope that helps..
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ur right ... ru sure abt the OA? whats the source...arorag wrote:lets say y=5, then y+ 4= 9
now to satisfy stat.I x> 9
lets assume x= 10
Now
is 3x>7y???
- blue_lotus
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Let us reprase the question
IS 3x > 7y
x > 2.33y ?
This is a YES/NO question
Now let us check option 1:
x > y + 4 : Insufficient as
it does not give us conclusive answer
Even if we try to plug numbers
when y = 1 , x = 5 , means x is greater than 2.33y YES
BUT when y = 4 , x = 8 , x is less than 2.33y NO
This means we cant get definite answer
check option 2:
-5x < -14y
x > 14/5y
x> 2.8 y
means x is greater than 2.333y
=> YES ( it can answer the question )
SUFFICIENT
ANSWER therefore is B: option 2 alone
IS 3x > 7y
x > 2.33y ?
This is a YES/NO question
Now let us check option 1:
x > y + 4 : Insufficient as
it does not give us conclusive answer
Even if we try to plug numbers
when y = 1 , x = 5 , means x is greater than 2.33y YES
BUT when y = 4 , x = 8 , x is less than 2.33y NO
This means we cant get definite answer
check option 2:
-5x < -14y
x > 14/5y
x> 2.8 y
means x is greater than 2.333y
=> YES ( it can answer the question )
SUFFICIENT
ANSWER therefore is B: option 2 alone