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

 It is currently 19 Oct 2019, 09:07

### 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

# If d1 and d2 are the numbers of defective items in production runs yie

Author Message
TAGS:

### Hide Tags

Math Expert
Joined: 02 Sep 2009
Posts: 58445
If d1 and d2 are the numbers of defective items in production runs yie  [#permalink]

### Show Tags

26 Aug 2019, 23:18
00:00

Difficulty:

25% (medium)

Question Stats:

83% (01:03) correct 17% (01:07) wrong based on 41 sessions

### HideShow timer Statistics

Competition Mode Question

If d1 and d2 are the numbers of defective items in production runs yielding r1 and r2 total items, respectively, the ratio of defects per run is greater for which of the two production runs?

(1) d1 > d2
(2) r2 > r1

_________________
Senior Manager
Joined: 18 May 2019
Posts: 363
Re: If d1 and d2 are the numbers of defective items in production runs yie  [#permalink]

### Show Tags

26 Aug 2019, 23:35
1
We are to determine which production run has a greater ratio of defects per run. d1 is defects in production 1 and d2 is defects in production 2. r1 is the runs in production 1 and r2 is the runs in production 2.

1 is insufficient because merely knowing d1>d2 is not enough to determine if d1/r1 is greater or otherwise than d2/r2.

2. Is also insufficient because it only tells us r2>r1. We need information on d1 and d2 in order to make a judgement.

1+2 clearly is sufficient.
Numerator d1>d2 and denominator r1<r2, hence d1/r1>d2/r2. We can therefore conclude that the defects per runs in production 1 is higher than that for production 2.

Posted from my mobile device
Manager
Joined: 01 Mar 2019
Posts: 164
Location: India
Concentration: Strategy, Social Entrepreneurship
Schools: Ross '22, ISB '20, NUS '20
GPA: 4
Re: If d1 and d2 are the numbers of defective items in production runs yie  [#permalink]

### Show Tags

26 Aug 2019, 23:41
1
We have to find the ratio of defects per run of the two production runs i.e d1/r1 and d2/r2

From (1) d1 > d2 say 6>5

without knowing any info regarding r1 and r2 we cannot conclude anything, so clearly insufficient

From (2) r2 > r1 say 5>1

similarly, without knowing any info regarding d1 and d2 we cannot conclude anything, so clearly insufficient

From (1) , (2)
we can say that 6/1 > 5/3 so ans : (C)
_________________
Appreciate any KUDOS given
Senior Manager
Joined: 07 Mar 2019
Posts: 327
Location: India
GMAT 1: 580 Q43 V27
WE: Sales (Energy and Utilities)
Re: If d1 and d2 are the numbers of defective items in production runs yie  [#permalink]

### Show Tags

27 Aug 2019, 01:08
1
To find which ratio of defect per runs is greater it is to be identified whether d1 > or < d2 and r1 > or < r2 individually. Of course d1 < r1 and d2 < r2

(1) d1 > d2
Clearly, INSUFFICIENT.

(2) r2 > r1
Clearly, INSUFFICIENT.

Together Statement 1) and 2).

Refer table snapshot.

Thus, for sufficiency of $$\frac{d1}{r1} > \frac{d2}{r2}$$, d1 > d2 and r1 < r2 – Case 1.

And for sufficiency of $$\frac{d1}{r1} < \frac{d2}{r2}$$, d1 < d2 and r1 > r2 – Case 4.

I.e. for a ratio to be greater than other numerator has to be greater than the other and denominator should be lesser than the other.

Attachments

File comment: If d1 and d2 are the numbers

If d1 and d2 are the numbers .JPG [ 80.36 KiB | Viewed 501 times ]

_________________
Ephemeral Epiphany..!

GMATPREP1 590(Q48,V23) March 6, 2019
GMATPREP2 610(Q44,V29) June 10, 2019
GMATPREPSoft1 680(Q48,V35) June 26, 2019
SVP
Joined: 03 Jun 2019
Posts: 1728
Location: India
Re: If d1 and d2 are the numbers of defective items in production runs yie  [#permalink]

### Show Tags

27 Aug 2019, 01:35
1
Given: d1 & d2 are defects in production runs yielding r1 & r2 total items

Asked: Number of defects are greater for which of the two production runs?

(1) d1 >d2
Since relationship between r1 & r2 is unknown
NOT SUFFICIENT

(2) r2 > r1
Since relationship between d1 & d2 is unknown
NOT SUFFICIENT

Combining (1) & (2)
(1) d1>d2
(2) r2>r1
d1/r1 > d2/r2
Number of defects per run are greater for production run 1 than production run 2.
SUFFICIENT

IMO C

Posted from my mobile device
_________________
"Success is not final; failure is not fatal: It is the courage to continue that counts."

Please provide kudos if you like my post. Kudos encourage active discussions.

My GMAT Resources: -

Efficient Learning
All you need to know about GMAT quant

Tele: +91-11-40396815
Mobile : +91-9910661622
E-mail : kinshook.chaturvedi@gmail.com
GMAT Club Legend
Joined: 18 Aug 2017
Posts: 5020
Location: India
Concentration: Sustainability, Marketing
GPA: 4
WE: Marketing (Energy and Utilities)
Re: If d1 and d2 are the numbers of defective items in production runs yie  [#permalink]

### Show Tags

27 Aug 2019, 02:50
If d1 and d2 are the numbers of defective items in production runs yielding r1 and r2 total items, respectively, the ratio of defects per run is greater for which of the two production runs?

(1) d1 > d2
(2) r2 > r1
need to determine ratio r1/d1 and r2/d2

#1 d1>d2 but runs not given insufficient
#2
r2>r1 but defects not given insufficient
from 1&2
we can say that d1/r1> d2/r2
IMO C
Senior Manager
Joined: 10 Aug 2018
Posts: 335
Location: India
Concentration: Strategy, Operations
WE: Operations (Energy and Utilities)
Re: If d1 and d2 are the numbers of defective items in production runs yie  [#permalink]

### Show Tags

27 Aug 2019, 06:03
E is the answer. Because even on combining we will not get a single result.

Because if (d1/r1) and (d2/r2) are (4/6) & (2/3) then both are equal.
and if (d1/r1) and (d2/r2) are (4/6) & (1/3) then 1st is greater.
_________________
On the way to get into the B-school and I will not leave it until I win. WHATEVER IT TAKES.

" I CAN AND I WILL"

GMAT:[640 Q44, V34, IR4, AWA5]

Manager
Joined: 12 Mar 2019
Posts: 160
Re: If d1 and d2 are the numbers of defective items in production runs yie  [#permalink]

### Show Tags

27 Aug 2019, 12:22
IMO C
Statement 1 : InSufficient: Tells us about no of defect is greater in d 1>d2. But doesn't tell us total items, It may be possible that d1 > d2, but if r2>r1, ratio can reverse.
e.g : d1 : 10, d2: 6 : r1 : 50 ; r2 : 240
r1/d1 : 5 ::1 , but r2/d2 : 40::1 ,
2nd case: d1 : 10, d2: 6 : r1 : 50 ; r2 : 18
r1/d1 : 5 ::1 , but r2/d2 : 3::1 ,

Insufficient

Statement 2: r2>r1: doesn't tell about defects: Insufficient

Combined: We can eliminate 1 condition from statement 1 : and we have only 1 solution:
Re: If d1 and d2 are the numbers of defective items in production runs yie   [#permalink] 27 Aug 2019, 12:22
Display posts from previous: Sort by