GMAT Question of the Day - Daily to your Mailbox; hard ones only

It is currently 19 Oct 2018, 10:46

Close

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
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.

Close

Request Expert Reply

Confirm Cancel

Which of the following relationships must be inversely proportional to

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
TAGS:

Hide Tags

Math Revolution GMAT Instructor
User avatar
V
Joined: 16 Aug 2015
Posts: 6390
GMAT 1: 760 Q51 V42
GPA: 3.82
Premium Member
Which of the following relationships must be inversely proportional to  [#permalink]

Show Tags

New post 16 Apr 2018, 00:54
00:00
A
B
C
D
E

Difficulty:

  35% (medium)

Question Stats:

53% (00:50) correct 47% (00:51) wrong based on 88 sessions

HideShow timer Statistics

[GMAT math practice question]

Which of the following relationships must be inversely proportional to each other?

I. Work done and working time
II. Speed and Traveling Time
III. Profit and Cost

A. I only
B. II only
C. III only
D. II and III
E. I and II

_________________

MathRevolution: Finish GMAT Quant Section with 10 minutes to spare
The one-and-only World’s First Variable Approach for DS and IVY Approach for PS with ease, speed and accuracy.
"Only $99 for 3 month Online Course"
"Free Resources-30 day online access & Diagnostic Test"
"Unlimited Access to over 120 free video lessons - try it yourself"

Manager
Manager
User avatar
G
Joined: 14 Oct 2017
Posts: 249
GMAT 1: 710 Q44 V41
Which of the following relationships must be inversely proportional to  [#permalink]

Show Tags

New post 16 Apr 2018, 12:11
2
Inverse proportion means that if x increases, y decreases.

Let's take a look at the three relationships:

I. Work done and working time -> If we increase the amount of work done there is no way the working time will decrease. The working time will likely increase, but it could also stay constant if we increase the work rate. However, the working time can not decrease.

II. Speed and traveling time -> If we increase the speed the traveling time must be reduced. Therefore, this is a valid choice.

III. Profit and cost -> If we increase the profit it doesn't have to cause a drop in costs. We could also increase our revenues. Hence, its not a valid choice because they don't have to be inversely proportional to each other

It follows that B) is the correct choice.

I hope that helps :-)
_________________

My goal: 700 GMAT score - REACHED :-) | My debrief - first attempt 710 (Q44,V41,IR7)

If I could help you with my answer, consider giving me Kudos

Senior Manager
Senior Manager
User avatar
G
Joined: 29 Dec 2017
Posts: 389
Location: United States
Concentration: Marketing, Technology
GMAT 1: 630 Q44 V33
GMAT 2: 690 Q47 V37
GMAT 3: 710 Q50 V37
GPA: 3.25
WE: Marketing (Telecommunications)
Re: Which of the following relationships must be inversely proportional to  [#permalink]

Show Tags

New post 16 Apr 2018, 13:39
Which of the following relationships must be inversely proportional to each other?

I. Work done and working time W=R*T
II. Speed and Traveling Time V=S/T
III. Profit and Cost P=R-C

Only V and 1/T are inversely proportional

B. II only
Target Test Prep Representative
User avatar
G
Status: Head GMAT Instructor
Affiliations: Target Test Prep
Joined: 04 Mar 2011
Posts: 2830
Re: Which of the following relationships must be inversely proportional to  [#permalink]

Show Tags

New post 17 Apr 2018, 16:28
MathRevolution wrote:
[GMAT math practice question]

Which of the following relationships must be inversely proportional to each other?

I. Work done and working time
II. Speed and Traveling Time
III. Profit and Cost

A. I only
B. II only
C. III only
D. II and III
E. I and II


If quantity x and quantity y are inversely proportional to each other, then xy = k where k is a constant.

If x = 3 and y = 8, then k = 24. If we change x to 4, then we have to change y to 6 in order to maintain k to be 24. Thus we see that in an inverse proportion, if one quantity increases, the other quantity decreases and vice versa.

Now let’s analyze each Roman numeral.

I. Work done and working time

If we have more working time, we have more work done. We see that one quantity increases and so does the other. This can’t be an inverse proportion.

II. Speed and Traveling Time

If we increase our speed, we shorten our traveling time when traveling for a fixed distance. For example, let’s say the distance is 120. If speed is 30, then time is 4; if speed is 40, then time is 3. We see that 30 x 4 = 40 x 3 = 120. We see that if one quantity increases then the other quantity must decrease. This is an inverse proportion.

III. Profit and Cost

If we increase the cost, we certainly decrease our profit. However, since profit and cost don’t multiply to be a fixed number, they are not in an inversely proportional relationship.

Answer: B
_________________

Jeffery Miller
Head of GMAT Instruction

GMAT Quant Self-Study Course
500+ lessons 3000+ practice problems 800+ HD solutions

Math Revolution GMAT Instructor
User avatar
V
Joined: 16 Aug 2015
Posts: 6390
GMAT 1: 760 Q51 V42
GPA: 3.82
Premium Member
Re: Which of the following relationships must be inversely proportional to  [#permalink]

Show Tags

New post 18 Apr 2018, 04:55
=>

Statement I
Let R be the work rate, W be the work done and T be the working time. Then R = W/T and T = W*R. Therefore, T and W are directly proportional.

Statement II
Let V be the speed, D be the distance and T be the traveling time. Then
V = D/T, and V and T are inversely proportional.

Statement III
Let P be the profit, R be the revenue and C be the cost. Then
P = R – C, and P and C are neither directly nor inversely proportional.

Therefore, B is the answer.

Answer B
_________________

MathRevolution: Finish GMAT Quant Section with 10 minutes to spare
The one-and-only World’s First Variable Approach for DS and IVY Approach for PS with ease, speed and accuracy.
"Only $99 for 3 month Online Course"
"Free Resources-30 day online access & Diagnostic Test"
"Unlimited Access to over 120 free video lessons - try it yourself"

GMAT Club Bot
Re: Which of the following relationships must be inversely proportional to &nbs [#permalink] 18 Apr 2018, 04:55
Display posts from previous: Sort by

Which of the following relationships must be inversely proportional to

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  


Copyright

GMAT Club MBA Forum Home| About| Terms and Conditions and Privacy Policy| GMAT Club Rules| Contact| Sitemap

Powered by phpBB © phpBB Group | Emoji artwork provided by EmojiOne

Kindly note that the GMAT® test is a registered trademark of the Graduate Management Admission Council®, and this site has neither been reviewed nor endorsed by GMAC®.