If y is an integer, is y 25 (2) y^3

Question

If y is an integer, is y < -5 ?

(1) y^2 > 25

(2) y^3 < -25

shridhar786 · Answer

y is an integer---- (given)

is y< -5?

STATEMENT (1)--- \(Y^2\)>25
(Y+5)(Y-5)>0
Y belongs to (-∞,-5)⋃(5,∞)
if y = -6 YES
if y = 6 NO
hence , INSUFFICIENT

STATEMENT (2)----\(y^3\)<-25
if y = -6 then YES
if y= -4 then NO
hence, INSUFFICIENT

combining both (1)&(2)
\(y^3\)<-25 is not valid if y belongs to (5,∞)
so possible value of y for both statements to be true (-∞,-5)
for y (-∞,-5) ---y is always <-5 so SUFFICIENT

C is the correct answer

arun8sharma · Answer

shridhar786 
Why won't it be B only?

As you have mentioned that y^3<-25. and by taking values of y< -6 and -4. Both are less than -25. so it gives a definite answer

bebs · Answer

shridhar786  You might want to check Statement 2 again. It looks like you missed something. The two numbers you tested should answer the prompt, no?

shridhar786 · Answer

we are asked is y<-5?

when we take y = -4 it satisfies y^3<-25

but it doesn't satisfy y<-5 since -4 is greater than -5 so here the answer is no and by statement 2 we don't get the definite answer so INSUFFICIENT

GOT IT

shridhar786 · Answer

hey  bebs 
can you point out what I missed here I think the 2 numbers I tested works well with the prompt

bebs · Answer

shridhar786  Oh. You are correct. I see the step I missed now. Thanks!

If y is an integer, is y < -5 ? (1) y^2 > 25 (2) y^3 < -25

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