Last visit was: 24 Apr 2025, 18:53 It is currently 24 Apr 2025, 18:53
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
User avatar
patanahi
Joined: 07 Jan 2011
Last visit: 17 Mar 2020
Posts: 13
Own Kudos:
14
 [7]
Given Kudos: 4
Posts: 13
Kudos: 14
 [7]
1
Kudos
Add Kudos
6
Bookmarks
Bookmark this Post
User avatar
subhashghosh
User avatar
Retired Moderator
Joined: 16 Nov 2010
Last visit: 25 Jun 2024
Posts: 900
Own Kudos:
Given Kudos: 43
Location: United States (IN)
Concentration: Strategy, Technology
Products:
Posts: 900
Kudos: 1,239
Kudos
Add Kudos
Bookmarks
Bookmark this Post
User avatar
patanahi
Joined: 07 Jan 2011
Last visit: 17 Mar 2020
Posts: 13
Own Kudos:
Given Kudos: 4
Posts: 13
Kudos: 14
Kudos
Add Kudos
Bookmarks
Bookmark this Post
User avatar
Spidy001
Joined: 01 Feb 2011
Last visit: 16 Feb 2015
Posts: 300
Own Kudos:
338
 [1]
Given Kudos: 42
Posts: 300
Kudos: 338
 [1]
1
Kudos
Add Kudos
Bookmarks
Bookmark this Post
1. Not sufficient.

sample of 10 items has 1 defective item. that doesnt tell us anything about the rest of the 4990 items.we may or may not have defective items in the rest.

2. Not sufficient.

sample of 100 items has 3 defective items. that doesnt tell us anything about the rest of 3900 items. we may or may not have defective items in the rest.

together , still not sufficient as we only about the defective items in a 100 item sample . we still dont know aything about the rest of the items.

Answer is E.
User avatar
GMATD11
Joined: 10 Nov 2010
Last visit: 25 Sep 2012
Posts: 128
Own Kudos:
Given Kudos: 22
Location: India
Concentration: Strategy, Operations
GMAT 1: 520 Q42 V19
GMAT 2: 540 Q44 V21
WE:Information Technology (Computer Software)
GMAT 2: 540 Q44 V21
Posts: 128
Kudos: 2,967
Kudos
Add Kudos
Bookmarks
Bookmark this Post
subhashghosh
(1) indicates 10% of batteries are defective

(2) indicates 3% of batteries are defective.

However, these are inconsistent, so we don't know for sure which of these two is full and accurate representation of shipment quality.

Answer - E.


Is this interpretation correct
User avatar
Bunuel
User avatar
Math Expert
Joined: 02 Sep 2009
Last visit: 24 Apr 2025
Posts: 100,914
Own Kudos:
719,262
 [3]
Given Kudos: 93,176
Products:
Expert
Expert reply
Active GMAT Club Expert! Tag them with @ followed by their username for a faster response.
Posts: 100,914
Kudos: 719,262
 [3]
3
Kudos
Add Kudos
Bookmarks
Bookmark this Post
GMATD11
subhashghosh
(1) indicates 10% of batteries are defective

(2) indicates 3% of batteries are defective.

However, these are inconsistent, so we don't know for sure which of these two is full and accurate representation of shipment quality.

Answer - E.


Is this interpretation correct

No, it's not. We can not extrapolate the data on some particular sample to all shipment.

What was the number of defective batteries in a shipment of 4000 batteries ?

(1) In a particular sample of 10 batteries selected from the shipment 1 was defective --> just tells us that there is at least 1 defective battery in the shipment of 4000 batteries. Not sufficient.

(2) In a particulare sample of 100 batteries selected from the shipment, 3 were defective --> just tells us that there are at least 3 defective batteries in the shipment of 4000 batteries. Not sufficient.

(1)+(2) All we know is that there are at least 3 defective batteries in the shipment of 4000 batteries. Not sufficient.

Answer; E.
User avatar
DhruvPatelD10
Joined: 21 Jan 2018
Last visit: 30 Oct 2024
Posts: 42
Own Kudos:
Given Kudos: 42
Location: India
GPA: 2.85
WE:Consulting (Consulting)
Posts: 42
Kudos: 23
Kudos
Add Kudos
Bookmarks
Bookmark this Post
patanahi
What was the number of defective batteries in a shipment of 4000 batteries ?

(1) In a particular sample of 10 batteries selected from the shipment 1 was defective.
(2) In a particulare sample of 100 batteries selected from the shipment, 3 were defective.

Option E

Because the question does not mention that the sample is an actual representaion of the whole lot.
User avatar
BrentGMATPrepNow
User avatar
Major Poster
Joined: 12 Sep 2015
Last visit: 13 May 2024
Posts: 6,765
Own Kudos:
Given Kudos: 799
Location: Canada
Expert
Expert reply
Posts: 6,765
Kudos: 33,431
Kudos
Add Kudos
Bookmarks
Bookmark this Post
patanahi
What was the number of defective batteries in a shipment of 4000 batteries ?

(1) In a particular sample of 10 batteries selected from the shipment 1 was defective.
(2) In a particulare sample of 100 batteries selected from the shipment, 3 were defective.

Target question: What was the number of defective batteries in a shipment of 4000 batteries?

Statement 1: In a particular sample of 10 batteries selected from the shipment, 1 was defective.
Don't make the mistake of assuming that this means 1/10 of ALL batteries are defective. There's no reason to assume this.
There are several scenarios that satisfy statement 1. Here are two:
Case a: There's 1 defective battery in the 10-battery sample, and 0 defective batteries in the remaining 3990 batteries. In this case, the answer to the target question is there's ONE defective battery in the shipment of 4000 batteries
Case b: There's 1 defective battery in the 10-battery sample, and 2 defective batteries in the remaining 3990 batteries. In this case, the answer to the target question is there are THREE defective batteries in the shipment of 4000 batteries
Since we cannot answer the target question with certainty, statement 1 is NOT SUFFICIENT

Statement 2: In a particular sample of 100 batteries selected from the shipment, 3 were defective.
There are several scenarios that satisfy statement 2. Here are two:
Case a: There are 3 defective batteries in the 100-battery sample, and 0 defective batteries in the remaining 3900 batteries. In this case, the answer to the target question is there are THREE defective batteries in the shipment of 4000 batteries
Case b: There are 3 defective batteries in the 100-battery sample, and 2 defective batteries in the remaining 3900 batteries. In this case, the answer to the target question is there are FIVE defective batteries in the shipment of 4000 batteries
Since we cannot answer the target question with certainty, statement 2 is NOT SUFFICIENT

Statements 1 and 2 combined
There are several scenarios that satisfy BOTH statements. Here are two:
Case a: 1 defective battery in 1st sample, 3 defective batteries in 2nd sample, and 0 defective batteries in the remaining 3890 batteries. In this case, the answer to the target question is there are FOUR defective batteries in the shipment of 4000 batteries
Case b: 1 defective battery in 1st sample, 3 defective batteries in 2nd sample, and 4 defective batteries in the remaining 3890 batteries. In this case, the answer to the target question is there are EIGHT defective batteries in the shipment of 4000 batteries
Since we cannot answer the target question with certainty, the combined statements are NOT SUFFICIENT

Answer: E

Cheers,
Brent
User avatar
bumpbot
User avatar
Non-Human User
Joined: 09 Sep 2013
Last visit: 04 Jan 2021
Posts: 36,932
Own Kudos:
Posts: 36,932
Kudos: 974
Kudos
Add Kudos
Bookmarks
Bookmark this Post
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.
Moderator:
Math Expert
100914 posts