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 Your Progress

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

Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.

It appears that you are browsing the GMAT Club forum unregistered!

Signing up is free, quick, and confidential.
Join other 350,000 members and get the full benefits of GMAT Club

Registration gives you:

Tests

Take 11 tests and quizzes from GMAT Club and leading GMAT prep companies such as Manhattan GMAT,
Knewton, and others. All are free for GMAT Club members.

Applicant Stats

View detailed applicant stats such as GPA, GMAT score, work experience, location, application
status, and more

Books/Downloads

Download thousands of study notes,
question collections, GMAT Club’s
Grammar and Math books.
All are free!

Thank you for using the timer!
We noticed you are actually not timing your practice. Click the START button first next time you use the timer.
There are many benefits to timing your practice, including:

in the above (1) is exactly a multiple for 4, so sufficient BUT in (2) if z = 0 , then x = 2, which when substituted in quest will not be divisible by 4. right? but the answer is D, both alone sufieicient

can anyone guide. do i have a wrong approach towards DS??

Re: data sufficiency [#permalink]
06 Feb 2012, 12:44

Expert's post

1

This post was BOOKMARKED

kashishh wrote:

if x is a +ve integer, is x³ - 3x² + 2x divisible by 4? (1) x = 4y + 4, where y is an integer (2) x = 2z + 2, where z is an integer

in the above (1) is exactly a multiple for 4, so sufficient BUT in (2) if z = 0 , then x = 2, which when substituted in quest will not be divisible by 4. right? but the answer is D, both alone sufieicient

can anyone guide. do i have a wrong approach towards DS??

If x is a positive integer , is x^3 - 3x^2+2x divisible by 4?

(1) x=4y+4, where y is an integer --> since x itself is divisible by 4 then x^3-3x^2+2x is divisible by 4. Sufficient.

(2) x=2z+2, where z is an integer --> x^3-3x^2+2x=x(x^2-3x+2)=(2z+2)(4z^2+8z+4-6z-6+2)=4(z+1)(2z^2+z) --> hence this expression is divisible by 4. Sufficient.

Answer: D.

As for your question: if x=2 then x^3-3x^2+2x=0. Now, zero is divisible by EVERY integer except zero itself, as 0/integer=integer.

Re: data sufficiency [#permalink]
11 Jan 2014, 16:37

Bunuel wrote:

kashishh wrote:

if x is a +ve integer, is x³ - 3x² + 2x divisible by 4? (1) x = 4y + 4, where y is an integer (2) x = 2z + 2, where z is an integer

in the above (1) is exactly a multiple for 4, so sufficient BUT in (2) if z = 0 , then x = 2, which when substituted in quest will not be divisible by 4. right? but the answer is D, both alone sufieicient

can anyone guide. do i have a wrong approach towards DS??

If x is a positive integer , is x^3 - 3x^2+2x divisible by 4?

(1) x=4y+4, where y is an integer --> since x itself is divisible by 4 then x^3-3x^2+2x is divisible by 4. Sufficient.

(2) x=2z+2, where z is an integer --> x^3-3x^2+2x=x(x^2-3x+2)=(2z+2)(4z^2+8z+4-6z-6+2)=4(z+1)(2z^2+z) --> hence this expression is divisible by 4. Sufficient.

Answer: D.

As for your question: if x=2 then x^3-3x^2+2x=0. Now, zero is divisible by EVERY integer except zero itself, as 0/integer=integer.

For the second statement could one only say that since x is a multiple of 2 and thus even then x-2 will also be even and that means that E*E = E and multiple of 4?

in the above (1) is exactly a multiple for 4, so sufficient BUT in (2) if z = 0 , then x = 2, which when substituted in quest will not be divisible by 4. right? but the answer is D, both alone sufieicient

can anyone guide. do i have a wrong approach towards DS??

Bunuel - could we have solved/approached the question this way?

Given the question stem - x^3-3x^2+2x - factor out an "x" and apply the FOIL method --> therefore we are left with x(x^2 - 3x +2x) = 0 --> x(x - 2)(x - 1) Therefore, x must equal 0, 1, or 2

With that said, plug in the values of 0, 1, and 2 into each of statement one and two to determine if they are sufficient Statement 1 --> only 0 works Statement 2 --> both 0 and 2 work (due to the value being an integer)

Therefore, OA is D because we can determine what exact values of of the question stems can be valid.

Let me know what you think, just trying to help out with different ways to approach this question.

in the above (1) is exactly a multiple for 4, so sufficient BUT in (2) if z = 0 , then x = 2, which when substituted in quest will not be divisible by 4. right? but the answer is D, both alone sufieicient

can anyone guide. do i have a wrong approach towards DS??

Bunuel - could we have solved/approached the question this way?

Given the question stem - x^3-3x^2+2x - factor out an "x" and apply the FOIL method --> therefore we are left with x(x^2 - 3x +2x) = 0 --> x(x - 2)(x - 1) Therefore, x must equal 0, 1, or 2

With that said, plug in the values of 0, 1, and 2 into each of statement one and two to determine if they are sufficient Statement 1 --> only 0 works Statement 2 --> both 0 and 2 work (due to the value being an integer)

Therefore, OA is D because we can determine what exact values of of the question stems can be valid.

Let me know what you think, just trying to help out with different ways to approach this question.

Your approach is not correct. Notice that we are NOT told that x^3-3x^2+2x is 0, thus your derivation that x is 0, 1, or 2 is not right. _________________

Re: data sufficiency [#permalink]
29 Jan 2014, 14:47

Bunuel wrote:

kashishh wrote:

if x is a +ve integer, is x³ - 3x² + 2x divisible by 4? (1) x = 4y + 4, where y is an integer (2) x = 2z + 2, where z is an integer

in the above (1) is exactly a multiple for 4, so sufficient BUT in (2) if z = 0 , then x = 2, which when substituted in quest will not be divisible by 4. right? but the answer is D, both alone sufieicient

can anyone guide. do i have a wrong approach towards DS??

If x is a positive integer , is x^3 - 3x^2+2x divisible by 4?

(1) x=4y+4, where y is an integer --> since x itself is divisible by 4 then x^3-3x^2+2x is divisible by 4. Sufficient.

(2) x=2z+2, where z is an integer --> x^3-3x^2+2x=x(x^2-3x+2)=(2z+2)(4z^2+8z+4-6z-6+2)=4(z+1)(2z^2+z) --> hence this expression is divisible by 4. Sufficient.

Answer: D.

As for your question: if x=2 then x^3-3x^2+2x=0. Now, zero is divisible by EVERY integer except zero itself, as 0/integer=integer.

Re: data sufficiency [#permalink]
29 Jan 2014, 21:52

Expert's post

jlgdr wrote:

Bunuel wrote:

kashishh wrote:

if x is a +ve integer, is x³ - 3x² + 2x divisible by 4? (1) x = 4y + 4, where y is an integer (2) x = 2z + 2, where z is an integer

in the above (1) is exactly a multiple for 4, so sufficient BUT in (2) if z = 0 , then x = 2, which when substituted in quest will not be divisible by 4. right? but the answer is D, both alone sufieicient

can anyone guide. do i have a wrong approach towards DS??

If x is a positive integer , is x^3 - 3x^2+2x divisible by 4?

(1) x=4y+4, where y is an integer --> since x itself is divisible by 4 then x^3-3x^2+2x is divisible by 4. Sufficient.

(2) x=2z+2, where z is an integer --> x^3-3x^2+2x=x(x^2-3x+2)=(2z+2)(4z^2+8z+4-6z-6+2)=4(z+1)(2z^2+z) --> hence this expression is divisible by 4. Sufficient.

Answer: D.

As for your question: if x=2 then x^3-3x^2+2x=0. Now, zero is divisible by EVERY integer except zero itself, as 0/integer=integer.

Re: If x is a positive integer, is x^3-3x^2+2x divisible by 4? [#permalink]
31 Mar 2015, 06:16

Hello from the GMAT Club BumpBot!

Thanks to another GMAT Club member, I have just discovered this valuable topic, yet it had no discussion for over a year. I am now bumping it up - doing my job. I think you may find it valuable (esp those replies with Kudos).

Want to see all other topics I dig out? Follow me (click follow button on profile). You will receive a summary of all topics I bump in your profile area as well as via email. _________________

Hello everyone! Researching, networking, and understanding the “feel” for a school are all part of the essential journey to a top MBA. Wouldn’t it be great... ...

As part of our focus on MBA applications next week, which includes a live QA for readers on Thursday with admissions expert Chioma Isiadinso, we asked our bloggers to...

Booth allows you flexibility to communicate in whatever way you see fit. That means you can write yet another boring admissions essay or get creative and submit a poem...