grandh01 wrote:Is x < y?
(1) z < y
(2) z < x

oa is A

The OA you provided is not correct. Either A alone or B alone is clearly not sufficient to say if x<y.

Combined: If z=3, y=8, and x=5, then x<y.
If z=3, y=5, and x=8, then x>y. NOT SUF.

Ans E.

Grandh - can you recheck the OA

Is x < y?

(1) z < y

No mention of x. So, statememt I is not sufficient to answer the question.

(2) z < x

No mention of y. So, statememt II is not sufficient to answer the question.

Statement I + II

Case I: Let (x,y,z) be (3,2,1) respectively. It satisfies both the conditions z<y(1<2) and z<x(1<3). In this case, x>y(3>2).
Case II: Let (x,y,z) be (2,3,1) respectively. It satisfies both the conditions z<y(1<3) and z<x(1<2). In this case, x<y(2<3).

As Statement I and Statement II combined isn't sufficient to answer the question, the correct answer choice should E

grandh01 wrote:Is x < y?
(1) z < y
(2) z < x

I think the correct answer should be E and here's why:

Question: is x<y
Statement 1: z<y is insufficient because we don't know anything about x nor about it's relationship with y.

Statement 2: z<x is insufficient because we don't know anything about y nor about it's relationship with x.

Together: They are both insufficient because we don't know how x and y relate to each other. For example it could be z<x<y or z<y<x both of these equations satisfy 1 and 2. Thus, this is not sufficient.