x and y on different sides of zero point

This topic has expert replies
User avatar
Master | Next Rank: 500 Posts
Posts: 117
Joined: Wed Dec 30, 2009 1:57 pm
Location: India
Thanked: 4 times
Followed by:1 members

x and y on different sides of zero point

by abhi332 » Wed Feb 24, 2010 5:02 am
In the number line, are x and y on different sides of zero point?

1). The distance from x to zero is equal to the distance from y to 1
2). The sum of the distance from x to zero and the distance from y to 1 is less than 1
What you think, you become.
Source: — Data Sufficiency |

Legendary Member
Posts: 610
Joined: Fri Jan 15, 2010 12:33 am
Thanked: 47 times
Followed by:2 members

by kstv » Wed Feb 24, 2010 6:25 am
IMO E

User avatar
Master | Next Rank: 500 Posts
Posts: 102
Joined: Sat Feb 20, 2010 5:38 am
Location: IIM Ahmedabad
Thanked: 10 times

by firdaus117 » Wed Feb 24, 2010 11:03 am
It's Option E
Note that it is not necessary that x and y are integers only.They can be any real numbers on the number line.
x=-0.25 and y=0.75 AND x=0.25 and y=0.75.These two sets of values satisfy both conditions yet they are respectively on opp. sides and same sides of zero point. :)

Master | Next Rank: 500 Posts
Posts: 194
Joined: Thu Jan 14, 2010 5:18 am
Thanked: 2 times

by girish3131 » Thu Feb 25, 2010 5:26 am
@Abhi

Good Ques...

IMO Ans is C

Plz put OA ...

Thanks!

User avatar
Master | Next Rank: 500 Posts
Posts: 117
Joined: Wed Dec 30, 2009 1:57 pm
Location: India
Thanked: 4 times
Followed by:1 members

by abhi332 » Thu Feb 25, 2010 5:34 am
[spoiler]OA: E[/spoiler]
What you think, you become.

Senior | Next Rank: 100 Posts
Posts: 39
Joined: Thu Feb 25, 2010 7:04 am
Thanked: 2 times

by sairamGmat » Thu Feb 25, 2010 8:15 am
I think

Let dx be the distance from x to 0 and dy be the distance from y to 1

Then, from (1) dx = dy [scenarios like x is 0.1 and y is 0.9 where the distance from x to 0 is 0.1 and y to 1 is 0.1 and also
it can be x is -0.2 and y is 0.8.]
so, this is InSufficient
from (2) dx+dy < 1
i.e. |(0-x) | + | 1-y| < 1 . With the same example above we cant really determine if x and y lie on the different sides
X and y can be 0.1 and 0.9 where dx+dy = 0.1 + 0.1 = 0.2 < 1
X and y can be -0.2 and 0.8 in which case dx+dy = 0.2 + 0.2 = 0.4 < 1 INSUFFICIENT

Combining both, dx = dy
dx+dy <1
2dx < 1
dx < 1/2
That means, distance from x to 0 is less than 1/2. so, x can be on either side of the zero before 0.5. Similarly, y
can be also the same dy < 1/2, which means y can also be on either side of the zero. INSUFFICIENT

IMO, E is the answer.

:!: