It is currently 19 Apr 2018, 08:29
Search
Register
GMAT Club Tests
Decision Tracker
My Rewards
New posts
Unanswered

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.

Go to My Workbook Learn more
Close

Request Expert Reply

Confirm Cancel

Events & Promotions

Events & Promotions in June
Open Detailed Calendar
CLICK HERE TO HIDE/SHOW EVENTS

The ratio of television sets to radios at an electronic store before

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  
  Sort by Date Sort by Kudos  
Search for:
 
Print view
First unread post
Author Message
TAGS:

Hide Tags
Expert Post
1 KUDOS received
Math Expert
User avatar
V
Joined: 02 Sep 2009
Posts: 44566
Premium Member CAT Tests
Top Member of the Month
The ratio of television sets to radios at an electronic store before [#permalink]

Show Tags

New post 16 Sep 2015, 04:17
1
This post received
KUDOS
Expert's post
00:00
A
B
C
D
E

Difficulty:

  55% (hard)

Question Stats:

61% (01:13) correct 39% (01:09) wrong based on 123 sessions

HideShow timer Statistics

The ratio of television sets to radios at an electronic store before a new shipment arrives is 12:7. If no television sets or radios leave the store and the only television sets and radios that arrive are in the new shipment, what is the ratio of television sets to radios after the new shipment arrives?

(1) The new shipment contains 132 television sets
(2) The new shipment contains 77 radios

Kudos for a correct solution.
[Reveal] Spoiler: OA

_________________

New to the Math Forum?
Please read this: Ultimate GMAT Quantitative Megathread | All You Need for Quant | PLEASE READ AND FOLLOW: 12 Rules for Posting!!!

Resources:
GMAT Math Book | Triangles | Polygons | Coordinate Geometry | Factorials | Circles | Number Theory | Remainders; 8. Overlapping Sets | PDF of Math Book; 10. Remainders | GMAT Prep Software Analysis | SEVEN SAMURAI OF 2012 (BEST DISCUSSIONS) | Tricky questions from previous years.

Collection of Questions:
PS: 1. Tough and Tricky questions; 2. Hard questions; 3. Hard questions part 2; 4. Standard deviation; 5. Tough Problem Solving Questions With Solutions; 6. Probability and Combinations Questions With Solutions; 7 Tough and tricky exponents and roots questions; 8 12 Easy Pieces (or not?); 9 Bakers' Dozen; 10 Algebra set. ,11 Mixed Questions, 12 Fresh Meat

DS: 1. DS tough questions; 2. DS tough questions part 2; 3. DS tough questions part 3; 4. DS Standard deviation; 5. Inequalities; 6. 700+ GMAT Data Sufficiency Questions With Explanations; 7 Tough and tricky exponents and roots questions; 8 The Discreet Charm of the DS; 9 Devil's Dozen!!!; 10 Number Properties set., 11 New DS set.


What are GMAT Club Tests?
Extra-hard Quant Tests with Brilliant Analytics

2 KUDOS received
Manager
Manager
avatar
Joined: 10 Aug 2015
Posts: 103
GMAT ToolKit User
Re: The ratio of television sets to radios at an electronic store before [#permalink]

Show Tags

New post 16 Sep 2015, 10:29
2
This post received
KUDOS
1
This post was
BOOKMARKED
Bunuel wrote:
The ratio of television sets to radios at an electronic store before a new shipment arrives is 12:7. If no television sets or radios leave the store and the only television sets and radios that arrive are in the new shipment, what is the ratio of television sets to radios after the new shipment arrives?

(1) The new shipment contains 132 television sets
(2) The new shipment contains 77 radios

Kudos for a correct solution.


Solution: Ratio = 12:7. Let x and y be no. of new TV sets and radios resp.
New ratio = 12k+x:7k+y which depends on x and y. We need both of them.

Statement1 : x = 132. Insufficient.

Statement2 : y = 77. Insufficient.

Combined : New ratio = 12k+132:7k+77 =12(k+11):7(k+11) = 12/7.Sufficient

Option C
1 KUDOS received
Director
Director
avatar
G
Joined: 21 May 2013
Posts: 621
Re: The ratio of television sets to radios at an electronic store before [#permalink]

Show Tags

New post 17 Sep 2015, 07:57
1
This post received
KUDOS
Bunuel wrote:
The ratio of television sets to radios at an electronic store before a new shipment arrives is 12:7. If no television sets or radios leave the store and the only television sets and radios that arrive are in the new shipment, what is the ratio of television sets to radios after the new shipment arrives?

(1) The new shipment contains 132 television sets
(2) The new shipment contains 77 radios

Kudos for a correct solution.


(1) The new shipment contains 132 television sets-Clearly Insufficient
(2) The new shipment contains 77 radios-Clearly Insufficient

Let us take numbers. If there are 12 TV's and 7 radios, then new ratio=(12+132)/7+77=144/84=12/7
If there are 120 TV's and 70 radios, then new ration=252/147=12/7
Answer C
Manager
Manager
avatar
Joined: 02 Jul 2015
Posts: 106
Schools: ISB '18
GMAT 1: 680 Q49 V33
Re: The ratio of television sets to radios at an electronic store before [#permalink]

Show Tags

New post 17 Sep 2015, 08:30
Answer is C


using 1 and 2 we can get the value of the new ratio.
Expert Post
Math Expert
User avatar
V
Joined: 02 Sep 2009
Posts: 44566
Premium Member CAT Tests
Top Member of the Month
Re: The ratio of television sets to radios at an electronic store before [#permalink]

Show Tags

New post 20 Sep 2015, 22:12
Expert's post
Bunuel wrote:
The ratio of television sets to radios at an electronic store before a new shipment arrives is 12:7. If no television sets or radios leave the store and the only television sets and radios that arrive are in the new shipment, what is the ratio of television sets to radios after the new shipment arrives?

(1) The new shipment contains 132 television sets
(2) The new shipment contains 77 radios

Kudos for a correct solution.


VERITAS PREP OFFICIAL SOLUTION:

Here, the trap answer is E. Note that it’s “satisfying” for you to be able to recall about ratios that, when only given an initial ratio and then adding a particular number, you cannot tell the impact on the new ratio (were there 19 appliances to start, or 19,000?). You can pat yourself on the back for knowing that about ratios, feel confident in your answer, and move on. But you haven’t spotted the “sucker” — which is that there’s one exception: If the numbers that you add are in the same ratio as the original, the ratio remains unchanged. And 132 TVs and 77 radios added is a ratio of 12:7 (each is a multiple of 11). So the correct answer is C — we can prove with both statements together that the ratio remains at 12:7.

And here is where the “spot the sucker” mentality can help you — that the answer is C probably does not present itself too clearly to anyone based on the numbers. But if you know to suspect a trap, and choice E seems to come a bit too easy, you know that you should spend some time investigating further. A common Data Sufficiency trap is for the test to give you an answer that comes with a little bit of satisfaction (“I know that rule!”) but that still doesn’t take much time or ingenuity to solve. Know that low levels of satisfaction are highly correlated with trap answers — use that as your cue to investigate just a bit further.
_________________

New to the Math Forum?
Please read this: Ultimate GMAT Quantitative Megathread | All You Need for Quant | PLEASE READ AND FOLLOW: 12 Rules for Posting!!!

Resources:
GMAT Math Book | Triangles | Polygons | Coordinate Geometry | Factorials | Circles | Number Theory | Remainders; 8. Overlapping Sets | PDF of Math Book; 10. Remainders | GMAT Prep Software Analysis | SEVEN SAMURAI OF 2012 (BEST DISCUSSIONS) | Tricky questions from previous years.

Collection of Questions:
PS: 1. Tough and Tricky questions; 2. Hard questions; 3. Hard questions part 2; 4. Standard deviation; 5. Tough Problem Solving Questions With Solutions; 6. Probability and Combinations Questions With Solutions; 7 Tough and tricky exponents and roots questions; 8 12 Easy Pieces (or not?); 9 Bakers' Dozen; 10 Algebra set. ,11 Mixed Questions, 12 Fresh Meat

DS: 1. DS tough questions; 2. DS tough questions part 2; 3. DS tough questions part 3; 4. DS Standard deviation; 5. Inequalities; 6. 700+ GMAT Data Sufficiency Questions With Explanations; 7 Tough and tricky exponents and roots questions; 8 The Discreet Charm of the DS; 9 Devil's Dozen!!!; 10 Number Properties set., 11 New DS set.


What are GMAT Club Tests?
Extra-hard Quant Tests with Brilliant Analytics

Expert Post
Math Expert
User avatar
V
Joined: 02 Sep 2009
Posts: 44566
Premium Member CAT Tests
Top Member of the Month
The ratio of television sets to radios at an electronics store before [#permalink]

Show Tags

New post 29 Sep 2015, 05:26
Expert's post
1
This post was
BOOKMARKED
The ratio of television sets to radios at an electronics store before a new shipment arrives is 12:7. If no television sets or radios leave the store, and the only television sets and radios that arrive are in the new shipment, what is the ratio of television sets to radios after the new shipment arrives?

(1) The new shipment contains 132 television sets.
(2) The new shipment contains 77 radios.

Kudos for a correct solution.
_________________

New to the Math Forum?
Please read this: Ultimate GMAT Quantitative Megathread | All You Need for Quant | PLEASE READ AND FOLLOW: 12 Rules for Posting!!!

Resources:
GMAT Math Book | Triangles | Polygons | Coordinate Geometry | Factorials | Circles | Number Theory | Remainders; 8. Overlapping Sets | PDF of Math Book; 10. Remainders | GMAT Prep Software Analysis | SEVEN SAMURAI OF 2012 (BEST DISCUSSIONS) | Tricky questions from previous years.

Collection of Questions:
PS: 1. Tough and Tricky questions; 2. Hard questions; 3. Hard questions part 2; 4. Standard deviation; 5. Tough Problem Solving Questions With Solutions; 6. Probability and Combinations Questions With Solutions; 7 Tough and tricky exponents and roots questions; 8 12 Easy Pieces (or not?); 9 Bakers' Dozen; 10 Algebra set. ,11 Mixed Questions, 12 Fresh Meat

DS: 1. DS tough questions; 2. DS tough questions part 2; 3. DS tough questions part 3; 4. DS Standard deviation; 5. Inequalities; 6. 700+ GMAT Data Sufficiency Questions With Explanations; 7 Tough and tricky exponents and roots questions; 8 The Discreet Charm of the DS; 9 Devil's Dozen!!!; 10 Number Properties set., 11 New DS set.


What are GMAT Club Tests?
Extra-hard Quant Tests with Brilliant Analytics

1 KUDOS received
Manager
Manager
avatar
Joined: 11 Sep 2013
Posts: 110
Schools: McCombs '19, Kenan-Flagler '17, SMU '17
The ratio of television sets to radios at an electronics store before [#permalink]

Show Tags

New post 29 Sep 2015, 05:51
1
This post received
KUDOS
Bunuel wrote:
The ratio of television sets to radios at an electronics store before a new shipment arrives is 12:7. If no television sets or radios leave the store, and the only television sets and radios that arrive are in the new shipment, what is the ratio of television sets to radios after the new shipment arrives?

(1) The new shipment contains 132 television sets.
(2) The new shipment contains 77 radios.

Kudos for a correct solution.


(1) The new shipment contains 132 television sets.

We do not know about RADIO in new shipment => DONT KNOW the ratio of television sets to radios after the new shipment arrives => INSUF
(2) The new shipment contains 77 radios
Do not know TV in new shipment => INSUF

(1) + (2) The ratio of television sets to radios after the new shipment arrives = (12a+132)/(7a+77)=12(a+11)/7(a+11) = 12/7
SUFFICIENT

Ans: C
Expert Post
1 KUDOS received
Manhattan Prep Instructor
User avatar
S
Joined: 22 Mar 2011
Posts: 1225
Re: The ratio of television sets to radios at an electronics store before [#permalink]

Show Tags

New post 29 Sep 2015, 14:18
1
This post received
KUDOS
Expert's post
This is basically a trick question. In order to know the new ratio of TVs to radios, we'd like to know the total numbers. When we see that each statement gives us numbers for the new shipments, we certainly want to know both those numbers--neither statement by itself is going to be sufficient. However, it seems obvious that without knowing how many TVs and radios are in the store to begin with, we can't tell how the shipment affects the total. This would make E look like the answer.

However, if we look at the ratio of the new shipment, it's still 12 to 7. This is the ONE situation in which we can know the new ratio without knowing the original numbers. If the new shipment is in the exact same ratio as we had before, then the ratio is unchanged. Sneaky . . .
_________________


Dmitry Farber | Manhattan GMAT Instructor | New York


Manhattan GMAT Discount | Manhattan GMAT Course Reviews | View Instructor Profile |
Manhattan GMAT Reviews

Expert Post
1 KUDOS received
Veritas Prep GMAT Instructor
User avatar
P
Joined: 16 Oct 2010
Posts: 8024
Location: Pune, India

Top Member of the Month
Re: The ratio of television sets to radios at an electronics store before [#permalink]

Show Tags

New post 29 Sep 2015, 22:00
1
This post received
KUDOS
Expert's post
1
This post was
BOOKMARKED
Bunuel wrote:
The ratio of television sets to radios at an electronics store before a new shipment arrives is 12:7. If no television sets or radios leave the store, and the only television sets and radios that arrive are in the new shipment, what is the ratio of television sets to radios after the new shipment arrives?

(1) The new shipment contains 132 television sets.
(2) The new shipment contains 77 radios.

Kudos for a correct solution.


This question is a caveat to blindly following the much hyped strategy of DS questions - if you can establish the sufficiency, do not solve the question.

There are cases where you need to look carefully before deciding whether the sufficiency condition is actually met. Some of them are:

1. Quadratic equations - Ensure that the roots are not the same. If they are the same, there could be a unique solution though you may not expect it.
2. Solving simultaneous equations - Ensure that the equations are not the same (e.g. one is a multiple of the other). There is no unique solution in this case.
3. Ratios - Ensure that the ratios are not the same. If they are, when you add them, the ratio stays the same.
_________________

Karishma
Veritas Prep | GMAT Instructor
My Blog

Get started with Veritas Prep GMAT On Demand for $199

Veritas Prep Reviews

Non-Human User
User avatar
Joined: 09 Sep 2013
Posts: 6641
Premium Member
Re: The ratio of television sets to radios at an electronic store before [#permalink]

Show Tags

New post 13 Apr 2018, 06:13
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.
_________________

GMAT Books | GMAT Club Tests | Best Prices on GMAT Courses | GMAT Mobile App | Math Resources | Verbal Resources

Re: The ratio of television sets to radios at an electronic store before   [#permalink] 13 Apr 2018, 06:13
Print view
First unread post
Display posts from previous: Sort by

The ratio of television sets to radios at an electronic store before

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

Moderators: chetan2u, VeritasPrepKarishma, mikemcgarry, Bunuel, amanvermagmat

Search for:


GMAT Club MBA Forum Home| About| Terms and Conditions| 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®.

Main navigation

GMAT Resources

Partners

MBA Resources

www.gmac.com|www.mba.com | | GMAT Club Rules | Terms and Conditions