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 [#permalink]

Show Tags

11 Feb 2011, 02:26

2

This post received KUDOS

22

This post was BOOKMARKED

00:00

A

B

C

D

E

Difficulty:

85% (hard)

Question Stats:

51% (02:36) correct
49% (02:07) wrong based on 1025 sessions

HideShow timer Statictics

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.

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

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 [#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 [#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. _________________

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

Material A costs $3 per kilogram, and Material B costs $5 [#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'?

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

Show Tags

28 Nov 2015, 07:59

2

This post received KUDOS

Expert's post

Alok322 wrote:

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'?

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 [#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?

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

Show Tags

16 Mar 2016, 07:35

1

This post received KUDOS

Expert's post

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.

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. _________________

So, my final tally is in. I applied to three b schools in total this season: INSEAD – admitted MIT Sloan – admitted Wharton – waitlisted and dinged No...

HBS alum talks about effective altruism and founding and ultimately closing MBAs Across America at TED: Casey Gerald speaks at TED2016 – Dream, February 15-19, 2016, Vancouver Convention Center...

By Libby Koerbel Engaging a room of more than 100 people for two straight hours is no easy task, but the Women’s Business Association (WBA), Professor Victoria Medvec...