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 500,000 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:

Material A costs $3 per kilogram, and Material B costs $5 per kilogram [#permalink]

Show Tags

11 Feb 2011, 02:26

3

This post received KUDOS

60

This post was BOOKMARKED

00:00

A

B

C

D

E

Difficulty:

85% (hard)

Question Stats:

50% (01:35) correct
50% (02:00) wrong based on 2295 sessions

HideShow timer Statistics

Material A costs $3 per kilogram, and Material B costs $5 per kilogram. If 10 kilograms of Material K consists of x kilograms of Material A and y kilograms of Material B, is x > y ?

(1) y > 4 (2) The cost of the 10 kilograms of Material K is less than $40.

Material A costs $3 per kilogram, and material B costs $5 per kilogram. If 10 kilograms of material K consists of x kilograms of material A and y kilograms of material B, is x >y?

(1) y > 4 (2) The cost of the 10 kilograms of material K is less than $40

Material A costs $3 per kilogram, and material B costs $5 per kilogram. If 10 kilograms of material K consists of x kilograms of material A and y kilograms of material B, is x >y?

Given: x+y=10. Question: is x>y?

(1) y > 4. Clearly insufficient: if y=4.5<x=5.5 the answer will be YES but if y=6>x=4 the answer will be NO.

(2) The cost of the 10 kilograms of material K is less than $40 ---> 3x+5y<40, as y=10-x then: 3x+5(10-x)<40 --> 2x>10 --> x>5, so x>y. Sufficient.

Re: Material A costs $3 per kilogram, and Material B costs $5 per kilogram [#permalink]

Show Tags

10 Mar 2011, 05:42

3

This post received KUDOS

Material A cost 3$/kg and B cost 5$/kg. If 10 kg of material K consist of x kg of A and y kg of B, is x>y?

1- y>4

2- the cost of 10kg of K is less than $40.

Solution: -

1) Insufficient Material A cost 3$/kg and B cost 5$/kg x+y=10 and y>4 is all we have from statement 1. Since the total price is not fixed, (x,y) can be anything satisfying x+y=10 ....even (5,5) can't be wrong in this case

2) Sufficient Material A cost 3$/kg and B cost 5$/kg x+y=10 and the cost of 10kg of K is less than $40. Therefore, 3x+5y<40 => 3x+(10-x)5<40 => 10<2x => 5<x So, x>5 and x+y=10 means x>y

Hope it helps !!!
_________________

Set out each day believing in your dreams. Know without a doubt that you were made for amazing things.

Material A costs $3 per kilogram, and material B costs $5 per kilogram. If 10 kilograms of material K consists of x kilograms of material A and y kilograms of material B, is x > y? (1) y > 4 (2) The cost of the 10 kilograms of material K is less than $40

Re: Material A costs $3 per kilogram, and Material B costs $5 per kilogram [#permalink]

Show Tags

16 Feb 2012, 08:47

5

This post received KUDOS

1

This post was BOOKMARKED

The answer has to be B.

Let's setup the weighted average equation for this question:

\(x\) kilograms at 3$ per Kilogram \(y\) kilograms at 5$ per Kilogram Yields \(10\) kilograms at z$ per Kilogram We also know that \(x+y=10\) So Equation would be : \(3(x)+5(y)=10(z)\)

Now let's look at the statements:

Statement 1: \(y>4\)

Remember: \(x+y=10\) So: \(x\) could range between 0 and 6. Insufficient

Statement 2: Cost is \(<40\)

So \(3(x)+5(y)<40\) But \(x+y=10\) so \(x=10-y\) So \(3(10-y)+5(y)<40\) So \(30-2y+5y<40\) So \(2y<10\) So \(y<5\)

If \(y<5\) then \(x>5\) so \(x>y\) Sufficient

Hence B _________________

"Nowadays, people know the price of everything, and the value of nothing."Oscar Wilde

Re: Material A costs $3 per kilogram, and Material B costs $5 per kilogram [#permalink]

Show Tags

15 Jun 2013, 14:13

2

This post received KUDOS

alltimeacheiver wrote:

Material A costs $3 per kilogram, and Material B costs $5 per kilogram. If 10 kilograms of Material K consists of x kilograms of Material A and y kilograms of Material B, is x > y ?

(1) y > 4 (2) The cost of the 10 kilograms of Material K is less than $40.

Material K cost "C" can be found out by calculating

C= (3*x+5*y)/10

Now the cost C will be close to Material A cost if x is more than y and vice versa

from St 1 we have y>4 For eg y=5, x=5 Cost of Material K will be $4/kg (in between price of Material A and Material B) now if x=4,y=6 ,Cost of material K will be be $ 4.2/kg if x=1,y=9 then Cost of material will be 4.8$ per kg but if we take y=4 and x=6 we get cost of material K as $ 3.8 per kg less than $ 4 which would have been the price had both material A and B were added equally.

Therefore if x>y we should have price of Material K < $ 4kg

Hence St1 alone not sufficient as we can have x=y or x<y

St 2, The cost of the 10 kilograms of Material K is less than $40.[/quote]

Cost of Material per kg <$4 which meets our above requirement which means x>y

Therefore ans st B
_________________

“If you can't fly then run, if you can't run then walk, if you can't walk then crawl, but whatever you do you have to keep moving forward.”

Re: Material A costs $3 per kilogram, and Material B costs $5 per kilogram [#permalink]

Show Tags

17 Jul 2014, 08:02

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.
_________________

WE: Supply Chain Management (Energy and Utilities)

Re: Material A costs $3 per kilogram, and Material B costs $5 per kilogram [#permalink]

Show Tags

27 Oct 2014, 02:21

Bunuel wrote:

alltimeacheiver wrote:

Material A costs $3 per kilogram, and material B costs $5 per kilogram. If 10 kilograms of material K consists of x kilograms of material A and y kilograms of material B, is x >y?

(1) y > 4 (2) The cost of the 10 kilograms of material K is less than $40

Material A costs $3 per kilogram, and material B costs $5 per kilogram. If 10 kilograms of material K consists of x kilograms of material A and y kilograms of material B, is x >y?

Given: x+y=10. Question: is x>y?

(1) y > 4. Clearly insufficient: if y=4.5<x=5.5 the answer will be YES but if y=6>x=4 the answer will be NO.

(2) The cost of the 10 kilograms of material K is less than $40 ---> 3x+5y<40, as y=10-x then: 3x+5(10-x)<40 --> 2x>10 --> x>5, so x>y. Sufficient.

Answer: B.

Bunuel, Can you, please, advise, if the problem stated that x and y can only be integers, would statement 1 be sufficient? I guess YES.

Re: Material A costs $3 per kilogram, and Material B costs $5 per kilogram [#permalink]

Show Tags

28 Nov 2015, 04:50

Bunuel wrote:

alltimeacheiver wrote:

Material A costs $3 per kilogram, and material B costs $5 per kilogram. If 10 kilograms of material K consists of x kilograms of material A and y kilograms of material B, is x >y?

(1) y > 4 (2) The cost of the 10 kilograms of material K is less than $40

Material A costs $3 per kilogram, and material B costs $5 per kilogram. If 10 kilograms of material K consists of x kilograms of material A and y kilograms of material B, is x >y?

Given: x+y=10. Question: is x>y?

(1) y > 4. Clearly insufficient: if y=4.5<x=5.5 the answer will be YES but if y=6>x=4 the answer will be NO.

(2) The cost of the 10 kilograms of material K is less than $40 ---> 3x+5y<40, as y=10-x then: 3x+5(10-x)<40 --> 2x>10 --> x>5, so x>y. Sufficient.

Answer: B.

Hi...If in the question it is mentioned that x and y are integers, then will the answer be D? because it will lead to contradiction that 'x is not greater than y' or will still answer be b because (there is no clarity whether x may be equal to y or may be less than y'?
_________________

Kudos is the best way to say Thank you! Please give me a kudos if you like my post

Material A costs $3 per kilogram, and material B costs $5 per kilogram. If 10 kilograms of material K consists of x kilograms of material A and y kilograms of material B, is x >y?

(1) y > 4 (2) The cost of the 10 kilograms of material K is less than $40

Material A costs $3 per kilogram, and material B costs $5 per kilogram. If 10 kilograms of material K consists of x kilograms of material A and y kilograms of material B, is x >y?

Given: x+y=10. Question: is x>y?

(1) y > 4. Clearly insufficient: if y=4.5<x=5.5 the answer will be YES but if y=6>x=4 the answer will be NO.

(2) The cost of the 10 kilograms of material K is less than $40 ---> 3x+5y<40, as y=10-x then: 3x+5(10-x)<40 --> 2x>10 --> x>5, so x>y. Sufficient.

Answer: B.

Hi...If in the question it is mentioned that x and y are integers, then will the answer be D? because it will lead to contradiction that 'x is not greater than y' or will still answer be b because (there is no clarity whether x may be equal to y or may be less than y'?

If we were told that x and y are integers then y > 4 (5, 6, 7, ...) together with x + y = 10, would be sufficient to say that x is NOT greater than y. But in this case the question would be flawed because the statements would contradict each other which never happens in proper GMAT DS questions.

Re: Material A costs $3 per kilogram, and Material B costs $5 per kilogram [#permalink]

Show Tags

23 Dec 2015, 07:42

Thank you Buennel!

Very important point since i came here with the same problem and i pulled my hair over this for a solid 20 minutes.

If you simplify (2) it results in y < 5. While (1) says that y > 4.

Contradicting? No. We might think its contradictory if we assume that the qty involved are integers (common mistake, since qty usually are).

Do note that the question does not say that x or y are integers. And it is for this reason, otherwise, the question would logically be incorrect.

My takeaway: 1) Always remember that GMAT statements are never contradictory 2) If at some point, it seems like they are contradicting, it could mean a) i've done it incorrectly b) they aren't contradicting in the first place! :p 3) In such WP questions, ask yourself, are the quantities divisible into decimals?

Material A costs $3 per kilogram, and Material B costs $5 per kilogram. If 10 kilograms of Material K consists of x kilograms of Material A and y kilograms of Material B, is x > y ?

(1) y > 4 (2) The cost of the 10 kilograms of Material K is less than $40.

Responding to a pm:

Quote:

In solving the B part of this question (like in many situation i have faced) 3[5]+5[5]=15+25="40<40" This is my question: [Q-1] Can we ever take 40<40 ie x<x when x is same number. Similarly x>x and so on in GMAT?

To be honest, I am not sure what your question means. 40 < 40 is not correct and neither is x < x since both are equal. And no, x > x doesn't work either. If they are the same number, one cannot be greater than the other. You might want to show me the steps of where you come across this problem.
_________________

Re: Material A costs $3 per kilogram, and Material B costs $5 per kilogram [#permalink]

Show Tags

17 Dec 2016, 11:31

Bunuel wrote:

alltimeacheiver wrote:

Material A costs $3 per kilogram, and material B costs $5 per kilogram. If 10 kilograms of material K consists of x kilograms of material A and y kilograms of material B, is x >y?

(1) y > 4 (2) The cost of the 10 kilograms of material K is less than $40

Material A costs $3 per kilogram, and material B costs $5 per kilogram. If 10 kilograms of material K consists of x kilograms of material A and y kilograms of material B, is x >y?

Given: x+y=10. Question: is x>y?

(1) y > 4. Clearly insufficient: if y=4.5<x=5.5 the answer will be YES but if y=6>x=4 the answer will be NO.

(2) The cost of the 10 kilograms of material K is less than $40 ---> 3x+5y<40, as y=10-x then: 3x+5(10-x)<40 --> 2x>10 --> x>5, so x>y. Sufficient.

Answer: B.

Hi Bunuel,

Can this be solve via weighted average? By the formulae n1/n2= (m2-m)/(m-m1)

Re: Material A costs $3 per kilogram, and Material B costs $5 per kilogram [#permalink]

Show Tags

08 Jan 2017, 18:51

I thought about this conceptually. Since A costs $3 per kg and B costs $5 per kg, I used that in conjunction with statement 2 to prove sufficiency. In statement 2, 10kg of K is less than $40. Dividing both sides by 10, 1 kg of K is less than $4. Knowing the costs of X and Y, that to me would mean that there would have to be more of A than B to be less than $4 (equal amounts would have it equal $4).

It's not perfect as we could be dealing with integers and you can't assume one of A or B isn't 0....but it's how I went about it.

Re: Material A costs $3 per kilogram, and Material B costs $5 per kilogram [#permalink]

Show Tags

30 Apr 2017, 19:45

Material A costs $3 per kilogram, and Material B costs $5 per kilogram. If 10 kilograms of Material K consists of x kilograms of Material A and y kilograms of Material B, is x > y ?

(1) y > 4 (2) The cost of the 10 kilograms of Material K is less than $40.

Re: Material A costs $3 per kilogram, and Material B costs $5 per kilogram [#permalink]

Show Tags

05 Aug 2017, 00:13

We can work this out using weighted average method as well.

Statement A: y>4 - clearly insufficient.

Statement B: Cost of 10kg of Material K is less than $40.

Cost of A is $3/kg and of B is $5/kg. Average cost of 10 kgs of combined material is <$4 ($40/10kgs). Using weighted average method:

3------------------------5 l------------4 Weighted average is less than 4, which means ratio of quantity of A:B i.e. x:y is skewed towards A. Thus, x>y.

We’ve given one of our favorite features a boost! You can now manage your profile photo, or avatar , right on WordPress.com. This avatar, powered by a service...

Sometimes it’s the extra touches that make all the difference; on your website, that’s the photos and video that give your content life. You asked for streamlined access...

A lot has been written recently about the big five technology giants (Microsoft, Google, Amazon, Apple, and Facebook) that dominate the technology sector. There are fears about the...

Post today is short and sweet for my MBA batchmates! We survived Foundations term, and tomorrow's the start of our Term 1! I'm sharing my pre-MBA notes...