BREAKING: Target Test Prep releases Brand New 2026 On Demand GMAT prep course

Redeem

Help me, plz..

This topic has expert replies
Post new topic Post Reply
Previous Topic Next Topic
Newbie | Next Rank: 10 Posts
Posts: 5
Joined: Thu Aug 07, 2008 7:42 am

Help me, plz..

by Goodlife » Fri Aug 15, 2008 9:12 pm
I tried to search thses question, but I can't.
What is the answer of these question?

===========================

If x + y is an integer, is y an integer?
(1) x – y is an integer.
(2) x + 2y is an integer.

===========================

Is x < y ?
(1) The ratio of x to y is 7/9.
(2) xy > 0

============================
Top
Source: — Data Sufficiency |
Legendary Member
Posts: 1153
Joined: Wed Jun 20, 2007 6:21 am
Thanked: 146 times
Followed by:2 members

by parallel_chase » Sat Aug 16, 2008 1:33 am
Ques 1

I think answer is B

x+y is integer is y an integer

Statement I

x-y is integer, this same as saying x+y is integer.

Insufficient.

Statement II

x+2y is integer, if x+y is integer & x+2y is integer, y and x both have to be integers.


Ques 2

I think the answer is E

Statement I

x and y are in ratio 7:9

for 63 x<y

for -63 x>y

Therefore insufficient.

Statement II

xy>0

x and y both are positive
or
x and y both are negative

Therefore, insufficient.

Combining I & II

xy>0
x/y=7/9

still have both the cases positive or negative.

Hence insufficient.

Whats are the OAs?
Top
Newbie | Next Rank: 10 Posts
Posts: 5
Joined: Mon Jun 16, 2008 9:54 pm

by classic » Sat Aug 16, 2008 8:50 am
Q 1

WHAT IF X=1 AND Y=0.5
THEN X+ 2Y= 1 +2*.5=2 AND INTEGER
Also X= 0.8 and Y=0.1

So B is also InSuff...

Opt 1.
X-Y will only be integer when x=y ( incase anyone or both x or y is non integer)

Wld go for C ( Both options are reqd.. to solve this problem)
Top
Legendary Member
Posts: 829
Joined: Mon Jul 07, 2008 10:09 pm
Location: INDIA
Thanked: 84 times
Followed by:3 members

by sudhir3127 » Sat Aug 16, 2008 10:36 am
classic wrote:Q 1

WHAT IF X=1 AND Y=0.5
THEN X+ 2Y= 1 +2*.5=2 AND INTEGER
Also X= 0.8 and Y=0.1

So B is also InSuff...

Opt 1.
X-Y will only be integer when x=y ( incase anyone or both x or y is non integer)

Wld go for C ( Both options are reqd.. to solve this problem)

"WHAT IF X=1 AND Y=0.5" this cannot happen because the question says X+Y is an integer and 1+0.5 is not an integer... so u cant that assumption..

hope its clear..
Top
Newbie | Next Rank: 10 Posts
Posts: 5
Joined: Thu Aug 07, 2008 7:42 am

Answers are..

by Goodlife » Sat Aug 16, 2008 10:38 am
1. B

2. E

-----------------------------
Thx for answer, from them, I understand Q1,
but Q2's condition 1).. I can't still get it.
Because
x : y = 7 : 9 <-- This mean that y is bigger than x, right?
so, I think the answer is A, not E.
But officially the answer is E.
This is my problem.
Top
Legendary Member
Posts: 829
Joined: Mon Jul 07, 2008 10:09 pm
Location: INDIA
Thanked: 84 times
Followed by:3 members

Re: Answers are..

by sudhir3127 » Sat Aug 16, 2008 10:45 am
Goodlife wrote:1. B

2. E

-----------------------------
Thx for answer, from them, I understand Q1,
but Q2's condition 1).. I can't still get it.
Because
x : y = 7 : 9 <-- This mean that y is bigger than x, right?
so, I think the answer is A, not E.
But officially the answer is E.
This is my problem.

I will try to explain u the 2nd question.
Is x < y ?
(1) The ratio of x to y is 7/9.
(2) xy > 0

if u take the first case... asssume that X is 49 and Y is 63
then the ratio is 7:9 and X<Y but what if X is -49 and Y is -63 .. even in that case the ratio is 7:9 but here X>Y.

so statement 1 is insufficient..

Statement 2 .. use the same number..
X=49, Y=63 XY>0 and X>Y

but if X=-49 and Y =-63 still XY>0 but X<Y

hence in sufficient .. Even with both ur not sure abt the signs of the numbers

Therefore the answer is E.

hope it helps.. do let me know if u have any doubts..
Top
Post new topic Post Reply
• Page 1 of 1