If x and y are positive, is 3x > 7y?
(1) x > y + 4
(2) -5x < -14y
[spoiler]
here i got B as the answer but the OA is D..
How statement 1 is sufficient?
take y=10, x=30 then 3x=90 and 7x=70
so 3x>7x..
now take y = 10, x = 15, therefore 3x = 45 and 7x = 70
so 3x<7x
please elaborate if i missed something..[/spoiler]
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positive integer
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Robinmrtha
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Statement 1
(1) x > y + 4
when y is less than 4, i.e. 2 then x is greater than 6
then the equation is 3x>7y: 18> 14 true....
when y is more than 4, i.e. 5 then x is 9
then 27>28 false...
insufficient
Statement 2
(2) -5x < -14y
or 5x>14y
or x>14y/5
or x >2.8y
from the question we have x > 2.3y
Since x >2.8y, then x > 2.3y
Sufficient
Answer B
(1) x > y + 4
when y is less than 4, i.e. 2 then x is greater than 6
then the equation is 3x>7y: 18> 14 true....
when y is more than 4, i.e. 5 then x is 9
then 27>28 false...
insufficient
Statement 2
(2) -5x < -14y
or 5x>14y
or x>14y/5
or x >2.8y
from the question we have x > 2.3y
Since x >2.8y, then x > 2.3y
Sufficient
Answer B
