Find all School-related info fast with the new School-Specific MBA Forum

It is currently 02 Sep 2014, 23:18

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.

Events & Promotions

Events & Promotions in June
Open Detailed Calendar

When the positive number a is rounded to the nearest tenth

  Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
TAGS:
4 KUDOS received
Intern
Intern
avatar
Status: I know my GPA is brilliant.
Joined: 03 Apr 2011
Posts: 36
WE 1: Big4 Assurance (2 years)
WE 2: Big4 M&A Advisory (2 years)
Followers: 0

Kudos [?]: 7 [4] , given: 7

When the positive number a is rounded to the nearest tenth [#permalink] New post 19 Sep 2012, 05:11
4
This post received
KUDOS
4
This post was
BOOKMARKED
00:00
A
B
C
D
E

Difficulty:

  45% (medium)

Question Stats:

56% (02:33) correct 44% (01:23) wrong based on 132 sessions
When the positive number a is rounded to the nearest tenth, the result is the number b. What is the tenths digit of a?

(1) When a is rounded to the nearest integer, the result is less than a.

(2) When b is rounded to the nearest integer, the result is greater than b.

Any suggestions?

Best,
[Reveal] Spoiler: OA
5 KUDOS received
Intern
Intern
User avatar
Joined: 01 Jul 2012
Posts: 11
Concentration: Finance, Healthcare
GMAT Date: 12-31-2012
GPA: 3.37
Followers: 1

Kudos [?]: 3 [5] , given: 10

Re: When the positive number a is rounded to the nearest tenth [#permalink] New post 19 Sep 2012, 06:25
5
This post received
KUDOS
Assume a = x.yz, b = x.t
(1) When a is rounded to the nearest integer, the result is less than a => y is equal to or less than 4. INSUFFICIENT.
(2) When b is rounded to the nearest integer, the result is greater than b. => t must be at least 5. We cannot find y.

(1) & (2): y must be 4 so that t will be at least 5 when a is rounded to the nearest tenth.
=> The answer is C.
_________________

Kaplan CAT 1 640 on 15/9/12

Intern
Intern
avatar
Status: I know my GPA is brilliant.
Joined: 03 Apr 2011
Posts: 36
WE 1: Big4 Assurance (2 years)
WE 2: Big4 M&A Advisory (2 years)
Followers: 0

Kudos [?]: 7 [0], given: 7

Re: When the positive number a is rounded to the nearest tenth [#permalink] New post 19 Sep 2012, 06:39
doraemonbeo wrote:
Assume a = x.yz, b = x.t
(1) When a is rounded to the nearest integer, the result is less than a => y is equal to or less than 4. INSUFFICIENT.
(2) When b is rounded to the nearest integer, the result is greater than b. => t must be at least 5. We cannot find y.

(1) & (2): y must be 4 so that t will be at least 5 when a is rounded to the nearest tenth.
=> The answer is C.


Thanks.

But when t is 5, if we round it to the nearest integer result will be higher than a.

Think about x.45

Round it to nearest tenth===> x.5
Round it to the nearest integer===>x+1

in that case result is higher than a. Am I missing some point?
1 KUDOS received
Intern
Intern
User avatar
Joined: 01 Jul 2012
Posts: 11
Concentration: Finance, Healthcare
GMAT Date: 12-31-2012
GPA: 3.37
Followers: 1

Kudos [?]: 3 [1] , given: 10

Re: When the positive number a is rounded to the nearest tenth [#permalink] New post 19 Sep 2012, 08:02
1
This post received
KUDOS
frankiegar wrote:
doraemonbeo wrote:
Assume a = x.yz, b = x.t
(1) When a is rounded to the nearest integer, the result is less than a => y is equal to or less than 4. INSUFFICIENT.
(2) When b is rounded to the nearest integer, the result is greater than b. => t must be at least 5. We cannot find y.

(1) & (2): y must be 4 so that t will be at least 5 when a is rounded to the nearest tenth.
=> The answer is C.


Thanks.

But when t is 5, if we round it to the nearest integer result will be higher than a.

Think about x.45

Round it to nearest tenth===> x.5
Round it to the nearest integer===>x+1

in that case result is higher than a. Am I missing some point?

t is the tenth digit of b, not a :) Moreover, you mustn't round it twice.
When x.45 is rounded to the nearest tenth, the result is x.5, but when it is rounded to the nearest integer, it is x.
_________________

Kaplan CAT 1 640 on 15/9/12

Intern
Intern
avatar
Status: I know my GPA is brilliant.
Joined: 03 Apr 2011
Posts: 36
WE 1: Big4 Assurance (2 years)
WE 2: Big4 M&A Advisory (2 years)
Followers: 0

Kudos [?]: 7 [0], given: 7

Re: When the positive number a is rounded to the nearest tenth [#permalink] New post 19 Sep 2012, 09:11
doraemonbeo wrote:
frankiegar wrote:
doraemonbeo wrote:
Assume a = x.yz, b = x.t
(1) When a is rounded to the nearest integer, the result is less than a => y is equal to or less than 4. INSUFFICIENT.
(2) When b is rounded to the nearest integer, the result is greater than b. => t must be at least 5. We cannot find y.

(1) & (2): y must be 4 so that t will be at least 5 when a is rounded to the nearest tenth.
=> The answer is C.


Thanks.

But when t is 5, if we round it to the nearest integer result will be higher than a.

Think about x.45

Round it to nearest tenth===> x.5
Round it to the nearest integer===>x+1

in that case result is higher than a. Am I missing some point?

t is the tenth digit of b, not a :) Moreover, you mustn't round it twice.
When x.45 is rounded to the nearest tenth, the result is x.5, but when it is rounded to the nearest integer, it is x.


Wow thanks my friend. :lol: Is it a rule in GMAT, the one about rounding twice?

Bc in statistics I always regard 0.45 as 1 if I round it :shock:
Expert Post
2 KUDOS received
Math Expert
User avatar
Joined: 02 Sep 2009
Posts: 25259
Followers: 3433

Kudos [?]: 25297 [2] , given: 2702

Re: When the positive number a is rounded to the nearest tenth [#permalink] New post 19 Sep 2012, 09:18
2
This post received
KUDOS
Expert's post
frankiegar wrote:
doraemonbeo wrote:
frankiegar wrote:

Thanks.

But when t is 5, if we round it to the nearest integer result will be higher than a.

Think about x.45

Round it to nearest tenth===> x.5
Round it to the nearest integer===>x+1

in that case result is higher than a. Am I missing some point?

t is the tenth digit of b, not a :) Moreover, you mustn't round it twice.
When x.45 is rounded to the nearest tenth, the result is x.5, but when it is rounded to the nearest integer, it is x.


Wow thanks my friend. :lol: Is it a rule in GMAT, the one about rounding twice?

Bc in statistics I always regard 0.45 as 1 if I round it :shock:


Rounding rules

Rounding is simplifying a number to a certain place value. To round the decimal drop the extra decimal places, and if the first dropped digit is 5 or greater, ROUND UP the last digit that you keep. If the first dropped digit is 4 or smaller, ROUND DOWN (keep the same) the last digit that you keep.

Example:
5.3485 rounded to the nearest tenth = 5.3, since the dropped 4 is less than 5.
5.3485 rounded to the nearest hundredth = 5.35, since the dropped 8 is greater than 5.
5.3485 rounded to the nearest thousandth = 5.349, since the dropped 5 is equal to 5.

For more check Number Theory chapter of Math Book: math-number-theory-88376.html

Hope it helps.
_________________

NEW TO MATH FORUM? PLEASE READ THIS: ALL YOU NEED FOR QUANT!!!

PLEASE READ AND FOLLOW: 11 Rules for Posting!!!

RESOURCES: [GMAT MATH BOOK]; 1. Triangles; 2. Polygons; 3. Coordinate Geometry; 4. Factorials; 5. Circles; 6. Number Theory; 7. Remainders; 8. Overlapping Sets; 9. PDF of Math Book; 10. Remainders; 11. GMAT Prep Software Analysis NEW!!!; 12. SEVEN SAMURAI OF 2012 (BEST DISCUSSIONS) NEW!!!; 12. Tricky questions from previous years. NEW!!!;

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?
25 extra-hard Quant Tests

Get the best GMAT Prep Resources with GMAT Club Premium Membership

Intern
Intern
avatar
Status: I know my GPA is brilliant.
Joined: 03 Apr 2011
Posts: 36
WE 1: Big4 Assurance (2 years)
WE 2: Big4 M&A Advisory (2 years)
Followers: 0

Kudos [?]: 7 [0], given: 7

Re: When the positive number a is rounded to the nearest tenth [#permalink] New post 19 Sep 2012, 09:22
Thanks bunuel.

Best,

Frankie.
Senior Manager
Senior Manager
User avatar
Joined: 13 Aug 2012
Posts: 464
Concentration: Marketing, Finance
GMAT 1: Q V0
GPA: 3.23
Followers: 14

Kudos [?]: 192 [0], given: 11

GMAT ToolKit User GMAT Tests User
Re: When the positive number a is rounded to the nearest tenth [#permalink] New post 19 Sep 2012, 21:32
frankiegar wrote:
When the positive number a is rounded to the nearest tenth, the result is the number b. What is the tenths digit of a?

(1) When a is rounded to the nearest integer, the result is less than a.

(2) When b is rounded to the nearest integer, the result is greater than b.

Any suggestions?

Best,


Let a = n.xy
Let b = n.r (r could be =x or =x+1)

What is x?

(1) a rounded becomes n. This means x is less than 1,2,3,4.
(2) b rounded becomes n+1. this means r is equal or greater than 5. Still haven't resolved whether r is equal to x or an increment of x.

Together,
(1) x is 1,2,3, or 4
(2) r is equal or greater than 5. But r is either an increment or equal x. It's obvious that r is not equal to its largest possible value 4. Then, r is an increment from 4. So x is 4.
_________________

Impossible is nothing to God.

Senior Manager
Senior Manager
avatar
Joined: 22 Dec 2011
Posts: 299
Followers: 3

Kudos [?]: 90 [0], given: 32

GMAT Tests User
When the positive number a is rounded to the nearest tenth [#permalink] New post 17 Oct 2012, 10:59
When the positive number a is rounded to the nearest tenth, the result is the number b. What is the tenths digit of a?

(1) When a is rounded to the nearest integer, the result is less than a.

(2) When b is rounded to the nearest integer, the result is greater than b.


OA
[Reveal] Spoiler:
C


Let a =x.yz what is y?

1/ When a is rounded to the nearest integer, the result is less than a. ->

so a can be x.01 to x.49 so tenths digit of a (i.e y) can be anywer between 0 to 4 NS

2/ When b is rounded to the nearest integer, the result is greater than b.

b=x.y so y can be anywer between 5 to 9.

What's wrong with my interpretation of statement 2?
Stat1 gives 0<= y < 4 and stat 2 gives 5 <= y < 9
Director
Director
User avatar
Joined: 22 Mar 2011
Posts: 613
WE: Science (Education)
Followers: 68

Kudos [?]: 507 [0], given: 43

GMAT Tests User
Re: When the positive number a is rounded to the nearest tenth [#permalink] New post 17 Oct 2012, 13:59
Jp27 wrote:
When the positive number a is rounded to the nearest tenth, the result is the number b. What is the tenths digit of a?

(1) When a is rounded to the nearest integer, the result is less than a.

(2) When b is rounded to the nearest integer, the result is greater than b.


OA
[Reveal] Spoiler:
C


Let a =x.yz what is y?

1/ When a is rounded to the nearest integer, the result is less than a. ->

so a can be x.01 to x.49 so tenths digit of a (i.e y) can be anywer between 0 to 4 NS

2/ When b is rounded to the nearest integer, the result is greater than b.

b=x.y so y can be anywer between 5 to 9.

What's wrong with my interpretation of statement 2?
Stat1 gives 0<= y < 4 and stat 2 gives 5 <= y < 9


so a can be x.01 to x.49 - 0<= y <= 4 - y can also be 4

(2) b=x.y - b was obtained by rounding a to the nearest tenth. So, the tenths digit of b isn't necessarily the same as the tenths digit of a.
We can just say that the tenths digit of b is at least 5.
_________________

PhD in Applied Mathematics
Love GMAT Quant questions and running.

Moderator
Moderator
User avatar
Joined: 02 Jul 2012
Posts: 1227
Location: India
Concentration: Strategy
GMAT 1: 740 Q49 V42
GPA: 3.8
WE: Engineering (Energy and Utilities)
Followers: 64

Kudos [?]: 666 [0], given: 116

Premium Member
Re: When the positive number a is rounded to the nearest tenth [#permalink] New post 18 Oct 2012, 03:19
1) the tenths digit of a could be 0,1,2,3,4. Insufficient
2) the tenths digit of b could be 5,6,7,8,9 and hence the tenths digit of a could be 4,5,6,7,8,9. Insufficient

1 & 2 together. Only one number overlaps both sets. So answer is 4 and hence C.
_________________

Did you find this post helpful?... Please let me know through the Kudos button.

Thanks To The Almighty - My GMAT Debrief

GMAT Reading Comprehension: 7 Most Common Passage Types

Intern
Intern
avatar
Joined: 01 Jun 2012
Posts: 26
Concentration: Entrepreneurship, Social Entrepreneurship
WE: Information Technology (Consulting)
Followers: 0

Kudos [?]: 5 [0], given: 4

Re: When the positive number a is rounded to the nearest tenth [#permalink] New post 18 Oct 2012, 09:37
Sorry, not getting this. if A=X.YZ, 'Y' is the unit place and 'Z' is the tenth place right?
if so, why not 'A' be say 5.61, then 'B' will be 5.6 and obviously 5.6<5.61
then 'C' will be 6 and obviously 6>5.6. So it is possible for the tenth place 'Z' from above to be anything from 0 through 4. Right? So the answer is 'E' right?
By looking at many of you confirming the answer to be 'C' I'm probably wrong. Please explain.
Director
Director
User avatar
Joined: 22 Mar 2011
Posts: 613
WE: Science (Education)
Followers: 68

Kudos [?]: 507 [0], given: 43

GMAT Tests User
Re: When the positive number a is rounded to the nearest tenth [#permalink] New post 18 Oct 2012, 09:48
1022lapog wrote:
Sorry, not getting this. if A=X.YZ, 'Y' is the unit place and 'Z' is the tenth place right?
if so, why not 'A' be say 5.61, then 'B' will be 5.6 and obviously 5.6<5.61
then 'C' will be 6 and obviously 6>5.6. So it is possible for the tenth place 'Z' from above to be anything from 0 through 4. Right? So the answer is 'E' right?
By looking at many of you confirming the answer to be 'C' I'm probably wrong. Please explain.



Sorry, not getting this. if A=X.YZ, 'Y' is the unit place and 'Z' is the tenth place right? - NO

X - units
Y - tenths
Z - hundreths
_________________

PhD in Applied Mathematics
Love GMAT Quant questions and running.

Senior Manager
Senior Manager
User avatar
Status: struggling with GMAT
Joined: 06 Dec 2012
Posts: 307
Location: Bangladesh
Concentration: Accounting
GMAT Date: 04-06-2013
GPA: 3.65
Followers: 8

Kudos [?]: 99 [0], given: 46

Re: When the positive number a is rounded to the nearest tenth [#permalink] New post 25 Feb 2013, 03:19
i have understand explanation of statement 1 and statement 2 but not understanding how c is answer.can u explain me in details plz
Manager
Manager
User avatar
Joined: 24 Sep 2012
Posts: 90
Location: United States
Concentration: Entrepreneurship, International Business
GMAT 1: 730 Q50 V39
GPA: 3.2
WE: Education (Education)
Followers: 3

Kudos [?]: 67 [0], given: 3

Re: When the positive number a is rounded to the nearest tenth [#permalink] New post 25 Feb 2013, 12:28
When the positive number a is rounded to the nearest tenth, the result is the number b. What is the tenths digit of a?

Let a=x.yz
b=x.n

Now, when a is rounded to the nearest tenth, the result is b. So, be must have only the tenth place in the decimal form and no hundreds place.

(1) When a is rounded to the nearest integer, the result is less than a.

Now, if rounding a to the nearest integer should give a value less than a, then y<=4. Consider a=5.41. Rounding a to the nearest tenth would give, a=5. However this is INSUFFICIENT to find the value of the tenth digit of a.

(2) When b is rounded to the nearest integer, the result is greater than b.

Now, when b is rounded to the nearest integer, the result >b. This is possible only if n>=5. Try a similar example as stated above

Together,

We need to find a with y<=4 and b with n>=5 so that when we round a to the nearest tenth, the answer is b.

The tenth value of b >=5. Now what possible value could a's tenth place have so that when it is rounded off, the value must be >=5. We know that the maximum value y could have is 4 and if z>5, then y could be rounded off to 5 right?

Hence, c is the solution.

Hope this helps! Let me know if I could help any further.

mun23 wrote:
i have understand explanation of statement 1 and statement 2 but not understanding how c is answer.can u explain me in details plz

_________________

Thanks
Kris
Instructor at Aspire4GMAT

Visit us at http://www.aspire4gmat.com

Post your queries
Join our free GMAT course

New blog: How to get that 700+
New blog: Data Sufficiency Tricks


Press Kudos if this helps!

SVP
SVP
User avatar
Joined: 09 Sep 2013
Posts: 2260
Followers: 187

Kudos [?]: 38 [0], given: 0

Premium Member
Re: When the positive number a is rounded to the nearest tenth [#permalink] New post 11 May 2014, 14:16
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

Senior Manager
Senior Manager
avatar
Joined: 15 Aug 2013
Posts: 275
Followers: 0

Kudos [?]: 10 [0], given: 23

Re: When the positive number a is rounded to the nearest tenth [#permalink] New post 26 May 2014, 11:33
MacFauz wrote:
1) the tenths digit of a could be 0,1,2,3,4. Insufficient
2) the tenths digit of b could be 5,6,7,8,9 and hence the tenths digit of a could be 4,5,6,7,8,9. Insufficient

1 & 2 together. Only one number overlaps both sets. So answer is 4 and hence C.


Hi MacFauz,

In statement 2, how do you get a to be 4,5,6,7,8,9 from knowing B? Wouldn't the tenths digit of a just be 4,5,6,7, and 8. It can't have a 9 in there or am I missing something?
Re: When the positive number a is rounded to the nearest tenth   [#permalink] 26 May 2014, 11:33
    Similar topics Author Replies Last post
Similar
Topics:
6 Experts publish their posts in the topic If x=y, is it true that x rounded to the nearest tenths is goodyear2013 3 24 Jun 2014, 14:35
If x is a positive number, rounded to the nearest integer, banksy 6 14 Feb 2011, 14:44
If x is a positive number, rounded to the nearest integer, nitya34 7 28 Mar 2009, 09:28
What would Rounding 1.545 to the nearest tenths give ? 1) ajay_gmat 2 07 Aug 2007, 23:05
What is the result when x is rounded to the nearest zoom 7 10 Sep 2005, 12:33
Display posts from previous: Sort by

When the positive number a is rounded to the nearest tenth

  Question banks Downloads My Bookmarks Reviews Important topics  


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

Powered by phpBB © phpBB Group and phpBB SEO

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®.