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

It is currently 21 Feb 2019, 04:29

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
Events & Promotions in February
PrevNext
SuMoTuWeThFrSa
272829303112
3456789
10111213141516
17181920212223
242526272812
Open Detailed Calendar
  • Online GMAT boot camp for FREE

     February 21, 2019

     February 21, 2019

     10:00 PM PST

     11:00 PM PST

    Kick off your 2019 GMAT prep with a free 7-day boot camp that includes free online lessons, webinars, and a full GMAT course access. Limited for the first 99 registrants! Feb. 21st until the 27th.
  • Free GMAT RC Webinar

     February 23, 2019

     February 23, 2019

     07:00 AM PST

     09:00 AM PST

    Learn reading strategies that can help even non-voracious reader to master GMAT RC. Saturday, February 23rd at 7 AM PT

The decimal representation of the number n is 0.ab where a and b are d

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

Hide Tags

 
Intern
Intern
avatar
B
Joined: 08 Jan 2019
Posts: 17
The decimal representation of the number n is 0.ab where a and b are d  [#permalink]

Show Tags

New post Updated on: 01 Feb 2019, 03:19
1
1
00:00
A
B
C
D
E

Difficulty:

  45% (medium)

Question Stats:

63% (01:46) correct 38% (01:39) wrong based on 31 sessions

HideShow timer Statistics

The decimal representation of the number n is 0.ab where a and b are distinct digits. What is the value of b?

(1) 8.2 < 10n < 8.7

(2) 4 < 5n < 4.2

Analyze the Question Stem:

This is a Value question. The digit b represents the hundredths digit of n, where a and b are distinct. For sufficiency, a single value for the hundredths place must be determined.

Evaluate the Statements:

Statement (1): The statement as it is presented, 8.2 < 10n < 8.7, can be simplified by dividing each component by 10. The possible range for n becomes 0.82 < n < 0.87. This means that b could be 3, 4, 5, or 6, and the statement is therefore Insufficient. Eliminate choices (A) and (D).

Statement (2): The statement as it is presented, 4 < 5n < 4.2, can be simplified by dividing each component by 5. The possible range for n becomes 0.8 < n < 0.84. Therefore b could be 1, 2, or 3, and the statement is Insufficient. Eliminate choice (B).

Combined: When taken together the statements are Sufficient. The only digit the two statements share in common is 3, which must be the value of b; Answer Choice (C) is correct.

Finding the logic quite convoluted which yields the answer E . thoughts?

Originally posted by DebbieChats on 01 Feb 2019, 03:15.
Last edited by Bunuel on 01 Feb 2019, 03:19, edited 1 time in total.
Renamed the topic and edited the question.
Math Expert
User avatar
V
Joined: 02 Sep 2009
Posts: 53061
The decimal representation of the number n is 0.ab where a and b are d  [#permalink]

Show Tags

New post 01 Feb 2019, 03:20
DebbieChats wrote:
The decimal representation of the number n is 0.ab where a and b are distinct digits. What is the value of b?

(1) 8.2 < 10n < 8.7

(2) 4 < 5n < 4.2

Analyze the Question Stem:

This is a Value question. The digit b represents the hundredths digit of n, where a and b are distinct. For sufficiency, a single value for the hundredths place must be determined.

Evaluate the Statements:

Statement (1): The statement as it is presented, 8.2 < 10n < 8.7, can be simplified by dividing each component by 10. The possible range for n becomes 0.82 < n < 0.87. This means that b could be 3, 4, 5, or 6, and the statement is therefore Insufficient. Eliminate choices (A) and (D).

Statement (2): The statement as it is presented, 4 < 5n < 4.2, can be simplified by dividing each component by 5. The possible range for n becomes 0.8 < n < 0.84. Therefore b could be 1, 2, or 3, and the statement is Insufficient. Eliminate choice (B).

Combined: When taken together the statements are Sufficient. The only digit the two statements share in common is 3, which must be the value of b; Answer Choice (C) is correct.

Finding the logic quite convoluted which yields the answer E . thoughts?


Please name topics properly (check rule 3 here: https://gmatclub.com/forum/rules-for-po ... 33935.html) and hide your doubts/questions under the spoilers. Thank you.
_________________

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

VP
VP
avatar
G
Joined: 09 Mar 2018
Posts: 1001
Location: India
Re: The decimal representation of the number n is 0.ab where a and b are d  [#permalink]

Show Tags

New post 01 Feb 2019, 03:39
DebbieChats wrote:
The decimal representation of the number n is 0.ab where a and b are distinct digits. What is the value of b?

(1) 8.2 < 10n < 8.7

(2) 4 < 5n < 4.2



Initially i had marked E, but if you look at the combination of both

1) 8.2 < 10n < 8.7
0.82 < n < 0.87, here n can be 0.8345 as well

2) 4 < 5n < 4.2
0.8 < n < 0.84, here n can 0.81 or 0.82 no fix value

Combine both the statements
Here n can be 0.83 or 0.823( I think this cannot exist for the question, because if we round this up to the hundredth place, it wont lie in the range of Statement 1)

Making it C.
_________________

If you notice any discrepancy in my reasoning, please let me know. Lets improve together.

Quote which i can relate to.
Many of life's failures happen with people who do not realize how close they were to success when they gave up.

Intern
Intern
avatar
B
Joined: 08 Jan 2019
Posts: 17
Re: The decimal representation of the number n is 0.ab where a and b are d  [#permalink]

Show Tags

New post 01 Feb 2019, 04:06
0.82 < n < 0.87 --- n = 0.83, 0.84, 0.85, 0.86
0.8 < n < 0.84 n = 0.81, 0.82, 0.83

From the above they are drawing the conclusion that last digit is 3 as 0.83 is the only overlap..

Apply that same logic to an inequality question

Statement 1 - a= 3 or -4
Statement 2 a< -2
1+2 the only overlap is -4 so a = -4 So choice should be C
Here the choice turns out to be E

GMAT logic is very illogical I have to say
VP
VP
avatar
G
Joined: 09 Mar 2018
Posts: 1001
Location: India
Re: The decimal representation of the number n is 0.ab where a and b are d  [#permalink]

Show Tags

New post 01 Feb 2019, 04:12
DebbieChats wrote:
0.82 < n < 0.87 --- n = 0.83, 0.84, 0.85, 0.86
0.8 < n < 0.84 n = 0.81, 0.82, 0.83

From the above they are drawing the conclusion that last digit is 3 as 0.83 is the only overlap..

Apply that same logic to an inequality question

Statement 1 - a= 3 or -4
Statement 2 a< -2
1+2 the only overlap is -4 so a = -4 So choice should be C

Here the choice turns out to be E

GMAT logic is very illogical I have to say


For the bold part the answer will be a C, only.

But for the question which you had posted previously, there the answer is E because
Statement 1 a= 3 or -4
Statement 2 a< -2 or a> 2 ( you have two range to satisfy)

Even after combining both the statements, you can get 2 values which satisfy both the ranges
3>2 yes and -2>-4 yes

But we were asked to find a value not values
making it an E
_________________

If you notice any discrepancy in my reasoning, please let me know. Lets improve together.

Quote which i can relate to.
Many of life's failures happen with people who do not realize how close they were to success when they gave up.

Math Expert
User avatar
V
Joined: 02 Sep 2009
Posts: 53061
Re: The decimal representation of the number n is 0.ab where a and b are d  [#permalink]

Show Tags

New post 01 Feb 2019, 04:13
DebbieChats wrote:
0.82 < n < 0.87 --- n = 0.83, 0.84, 0.85, 0.86
0.8 < n < 0.84 n = 0.81, 0.82, 0.83

From the above they are drawing the conclusion that last digit is 3 as 0.83 is the only overlap..

Apply that same logic to an inequality question

Statement 1 - a= 3 or -4
Statement 2 a< -2
1+2 the only overlap is -4 so a = -4 So choice should be C
Here the choice turns out to be E


GMAT logic is very illogical I have to say


GMAT is very precise.

I tried to explain what you are missing with highlighted question here: https://gmatclub.com/forum/what-is-the- ... l#p2218725
_________________

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

Manager
Manager
avatar
B
Joined: 01 Nov 2018
Posts: 72
GMAT 1: 690 Q48 V35
GPA: 3.88
Reviews Badge CAT Tests
Re: The decimal representation of the number n is 0.ab where a and b are d  [#permalink]

Show Tags

New post 02 Feb 2019, 05:57
Great Question. Have to play around with the numbers. First statement, 0.83,0.84, 0.85 work so not sufficient. Second statement, 0.82 and 0.83 work so not sufficient. Combined, also 0.83 works meaning b must be the digit 3, hence C.
GMAT Club Bot
Re: The decimal representation of the number n is 0.ab where a and b are d   [#permalink] 02 Feb 2019, 05:57
Display posts from previous: Sort by

The decimal representation of the number n is 0.ab where a and b are d

  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®.