It is currently 23 Oct 2017, 08:32

### GMAT Club Daily Prep

#### Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.

Customized
for You

we will pick new questions that match your level based on your Timer History

Track

every week, we’ll send you an estimated GMAT score based on your performance

Practice
Pays

we will pick new questions that match your level based on your Timer History

# Events & Promotions

###### Events & Promotions in June
Open Detailed Calendar

# is there a typo in this Q because it doesnt make any sense!!

Author Message
Intern
Joined: 09 Nov 2009
Posts: 20

Kudos [?]: 2 [0], given: 0

is there a typo in this Q because it doesnt make any sense!! [#permalink]

### Show Tags

10 Nov 2009, 06:59
00:00

Difficulty:

(N/A)

Question Stats:

0% (00:00) correct 0% (00:00) wrong based on 0 sessions

### HideShow timer Statistics

This topic is locked. If you want to discuss this question please re-post it in the respective forum.

If x=y≠4 and x=20-y, then$$x^2 - y^2$$ = ?

A- 16
B - 80
C - 144
D - 256
E - 384

The Q doesnt make sense .. if x=y then the result would be 0 ... is there a typo in the problem collection? Correct should be B (according to the book)

Thanks for ur help!

Last edited by elinka on 10 Nov 2009, 07:16, edited 1 time in total.

Kudos [?]: 2 [0], given: 0

VP
Joined: 05 Mar 2008
Posts: 1468

Kudos [?]: 301 [0], given: 31

Re: is there a typo in this Q because it doesnt make any sense!! [#permalink]

### Show Tags

10 Nov 2009, 07:06
If x=y(sign for different from)4 and x=20-y, then x^2 - y^2 = ?

A- 16
B - 80
C - 144
D - 256
E - 384

The Q doesnt make sense .. if x=y then the result would be 0 ... is there a typo in the problem collection? Correct should be B (according to the book)

Thanks for ur help!

If x=y(sign for different from)4

What does that mean?

Kudos [?]: 301 [0], given: 31

VP
Joined: 05 Mar 2008
Posts: 1468

Kudos [?]: 301 [0], given: 31

Re: is there a typo in this Q because it doesnt make any sense!! [#permalink]

### Show Tags

10 Nov 2009, 07:10
If x=y(sign for different from)4 and x=20-y, then x^2 - y^2 = ?

A- 16
B - 80
C - 144
D - 256
E - 384

The Q doesnt make sense .. if x=y then the result would be 0 ... is there a typo in the problem collection? Correct should be B (according to the book)

Thanks for ur help!

the only think i can figure is
x^2 - y^2 = (x+y)(x-y)

x + y = 20
x - y = 4

Kudos [?]: 301 [0], given: 31

Intern
Joined: 09 Nov 2009
Posts: 20

Kudos [?]: 2 [0], given: 0

Re: is there a typo in this Q because it doesnt make any sense!! [#permalink]

### Show Tags

10 Nov 2009, 07:14
it means .. x is equal to y is different from 4 ..... x=y≠4

Kudos [?]: 2 [0], given: 0

Math Expert
Joined: 02 Sep 2009
Posts: 41912

Kudos [?]: 129456 [0], given: 12201

Re: is there a typo in this Q because it doesnt make any sense!! [#permalink]

### Show Tags

10 Nov 2009, 07:20
it means .. x is equal to y is different from 4 ..... x=y≠4

If the correct answer is B (80) then there is a definitely a typo. The stem should state:

x=y+4 , x=20-y, x^2-y^2=?

Then the solution from lagomez is absolutely correct:
x=y+4 --> x-y=4
x=20-y --> x+y=20

x^2-y^2=(x-y)(x+y)=4*20=80.
_________________

Kudos [?]: 129456 [0], given: 12201

Intern
Joined: 09 Nov 2009
Posts: 20

Kudos [?]: 2 [0], given: 0

Re: is there a typo in this Q because it doesnt make any sense!! [#permalink]

### Show Tags

10 Nov 2009, 07:28
thanks, I wasnt sure if there was a catch since the question, in its "correct" form, seems way too simple ...

Kudos [?]: 2 [0], given: 0

Manager
Joined: 23 Jun 2009
Posts: 145

Kudos [?]: 14 [0], given: 9

Re: is there a typo in this Q because it doesnt make any sense!! [#permalink]

### Show Tags

12 Nov 2009, 02:15
Bunuel wrote:
it means .. x is equal to y is different from 4 ..... x=y≠4

If the correct answer is B (80) then there is a definitely a typo. The stem should state:

x=y+4 , x=20-y, x^2-y^2=?

Then the solution from lagomez is absolutely correct:
x=y+4 --> x-y=4
x=20-y --> x+y=20

x^2-y^2=(x-y)(x+y)=4*20=80.

Thanks Bunuel ..you r the best as always

Kudos [?]: 14 [0], given: 9

Re: is there a typo in this Q because it doesnt make any sense!!   [#permalink] 12 Nov 2009, 02:15
Display posts from previous: Sort by