|
Author |
Message |
|
TAGS:
|
|
|
Intern
Joined: 27 Sep 2009
Posts: 42
Followers: 0
Kudos [?]:
3
[0], given: 4
|
A terminating decimal is defined as a decimal that has a [#permalink]
22 May 2010, 14:35
Question Stats:
46% (01:50) correct
53% (00:50) wrong based on 26 sessions
A terminating decimal is defined as a decimal that has a finite number of nonzero digits. Examples of terminating decimals are 0.24, 52, and 6.0314. x and y are positive integers. If x/y is expressed as a decimal, is it a terminating decimal?
(1) 40 < x < 45
(2) y = 8
|
|
|
|
|
|
|
Manager
Joined: 16 Mar 2010
Posts: 120
Location: Halifax, Canada
Schools: Dalhousie School of Business (Corporate Residency MBA)
Followers: 5
Kudos [?]:
33
[0], given: 8
|
(1) Definitely isn't enough, because you can tweak the denominator any way you like to arrive at fraction that simplifies down to say, 2/3 (0.66666...) (2) Is the same thing. At first glance this question seems really too easy. You need to know what's going on with both x and y in order be able to answer it. C) jumps out immediately. It's obvious that if you know even the ranges of both x and y you could test each combo out and eventually arrive at an answer so clearly taken together they are sufficient. It's just a matter of seeing if A, B or D is feasible. I don't think they are for the reasons I gave above. If I only know either the nominator or denominator, I can find a match somewhere down the line that allows to make it so the simplified result ends up to be 2/3 (recurring decimal) or 1/1 (obviously a terminating one). So: C
_________________
I'm a current Corporate Residency MBA student at Dalhousie University (Nova Scotia, Canada). This account is to help spread the word about this unique program, as well as to help provide a student perspective for MBA applications and GMAT experiences.
Every week I publish a blog about life in the CRMBA by interviewing current students. Find us on Twitter and Facebook, or post any questions/comments/concerns in this thread here on gmatclub.com
Highlights of the program include:
Specifically designed by Corporations/Employers, No work experience necessary, 8-month paid corporate residency, Grades/GMAT score not the main focus for admittance
|
|
|
|
|
|
Intern
Joined: 27 Sep 2009
Posts: 42
Followers: 0
Kudos [?]:
3
[0], given: 4
|
dalmba wrote: (1) Definitely isn't enough, because you can tweak the denominator any way you like to arrive at fraction that simplifies down to say, 2/3 (0.66666...) (2) Is the same thing.
At first glance this question seems really too easy. You need to know what's going on with both x and y in order be able to answer it.
C) jumps out immediately. It's obvious that if you know even the ranges of both x and y you could test each combo out and eventually arrive at an answer so clearly taken together they are sufficient.
It's just a matter of seeing if A, B or D is feasible. I don't think they are for the reasons I gave above. If I only know either the nominator or denominator, I can find a match somewhere down the line that allows to make it so the simplified result ends up to be 2/3 (recurring decimal) or 1/1 (obviously a terminating one).
So: C OA is B Statement (2): Any number divided by 8 results in a terminating decimal. This is because when a number is divided by 2, the only possible remainders are or 1, 2, 3, 4, 5, 6, and 7 (actually 1/8, 2/8, etc.). These remainders are expressed as .125, .25, .375, .5, .625, .75, and .875, respectively. Therefore x/y is a terminating decimal; SUFFICIENT. I did not understand this... could u please help me
|
|
|
|
|
|
Manager
Joined: 16 Mar 2010
Posts: 120
Location: Halifax, Canada
Schools: Dalhousie School of Business (Corporate Residency MBA)
Followers: 5
Kudos [?]:
33
[0], given: 8
|
Haha, this is why I'm bad at DS. You're supposed to intuitively know that anything ever divided by 8 will result in a terminal decimal. I messed up in assuming I had control over the denominator (when I said (2) is the same logic as why (1) doesn't work), when it clearly said it was 8 and nothing else. It's funny, the last DS question I answered here I got right but made a big deal about feeling reluctant to toss out B. I was right to be feeling that way, but just not for the correct question. *sigh*
_________________
I'm a current Corporate Residency MBA student at Dalhousie University (Nova Scotia, Canada). This account is to help spread the word about this unique program, as well as to help provide a student perspective for MBA applications and GMAT experiences.
Every week I publish a blog about life in the CRMBA by interviewing current students. Find us on Twitter and Facebook, or post any questions/comments/concerns in this thread here on gmatclub.com
Highlights of the program include:
Specifically designed by Corporations/Employers, No work experience necessary, 8-month paid corporate residency, Grades/GMAT score not the main focus for admittance
|
|
|
|
|
|
Forum Moderator
Status: doing good things...
Joined: 02 Jul 2009
Posts: 1234
Concentration: Entrepreneurship, Finance
GMAT 1: Q V GMAT 2: 690 Q49 V35
GPA: 3.77
WE: Corporate Finance (Other)
Followers: 126
Kudos [?]:
419
[0], given: 523
|
shekar123 wrote: A terminating decimal is defined as a decimal that has a finite number of nonzero digits. Examples of terminating decimals are 0.24, 52, and 6.0314. x and y are positive integers. If x/y is expressed as a decimal, is it a terminating decimal?
(1) 40 < x < 45
(2) y = 8 B. any positive integer number divided by 8 gives terminate decimal equal to 5. 1) is very alluring, cause we read 1) and then 2), having in mind "I dont know x, so I cant find out what is the decimal point, thus I need to know the range of numbers for X" Thus c is wrong.
_________________
Follow me, if you find my explanations useful.
Audaces fortuna juvat!
Find out what's new at GMAT Club - latest features and updates
|
|
|
|
|
|
GMAT Club team member
Joined: 02 Sep 2009
Posts: 12116
Followers: 1879
Kudos [?]:
10126
[4] , given: 964
|
4
This post received KUDOS
Theory:Reduced fraction \frac{a}{b} (meaning that fraction is already reduced to its lowest term) can be expressed as terminating decimal if and only b (denominator) is of the form 2^n5^m, where m and n are non-negative integers. For example: \frac{7}{250} is a terminating decimal 0.028, as 250 (denominator) equals to 2*5^3. Fraction \frac{3}{30} is also a terminating decimal, as \frac{3}{30}=\frac{1}{10} and denominator 10=2*5. Note that if denominator already has only 2-s and/or 5-s then it doesn't matter whether the fraction is reduced or not.For example \frac{x}{2^n5^m}, (where x, n and m are integers) will always be terminating decimal. (We need reducing in case when we have the prime in denominator other then 2 or 5 to see whether it could be reduced. For example fraction \frac{6}{15} has 3 as prime in denominator and we need to know if it can be reduced.) In original question statement (2) says that denominator equals to 2^3=8, hence x/8 will be terminating decimal no matter what the value of x is.
_________________
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
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. NEW!!! ,11 Mixed Questions NEW!!!, 12 Fresh Meat NEW!!!
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. NEW!!!, 11 New DS set. NEW!!!
 What are GMAT Club Tests? 25 extra-hard Quant Tests
Find out what's new at GMAT Club - latest features and updates
|
|
|
|
|
|
Manager
Joined: 16 Mar 2010
Posts: 120
Location: Halifax, Canada
Schools: Dalhousie School of Business (Corporate Residency MBA)
Followers: 5
Kudos [?]:
33
[0], given: 8
|
Bunuel wrote: For example \frac{x}{2^n5^m}, (where x, n and m are integers) will always be terminating decimal.
That is sweet. A nifty little tool that's not too horrible to remember. Also, in order to preserve some sort of semblance of competency in this realm I will quite proudly point out that there was a typo in your post here: Bunuel wrote: as 250 (denominator) equals to 2*5^2. As it should read - " 250 (denominator) equals to 2*5^3"
_________________
I'm a current Corporate Residency MBA student at Dalhousie University (Nova Scotia, Canada). This account is to help spread the word about this unique program, as well as to help provide a student perspective for MBA applications and GMAT experiences.
Every week I publish a blog about life in the CRMBA by interviewing current students. Find us on Twitter and Facebook, or post any questions/comments/concerns in this thread here on gmatclub.com
Highlights of the program include:
Specifically designed by Corporations/Employers, No work experience necessary, 8-month paid corporate residency, Grades/GMAT score not the main focus for admittance
|
|
|
|
|
|
Senior Manager
Affiliations: SPG
Joined: 15 Nov 2006
Posts: 326
Followers: 10
Kudos [?]:
183
[0], given: 19
|
Re: 600 + question [#permalink]
22 May 2010, 21:58
shekar123 wrote: A terminating decimal is defined as a decimal that has a finite number of nonzero digits. Examples of terminating decimals are 0.24, 52, and 6.0314. x and y are positive integers. If x/y is expressed as a decimal, is it a terminating decimal?
(1) 40 < x < 45
(2) y = 8 1) we don't know anything about y, so Insufficient 2) when you divide anything by 8 the answer will be either an integer, a fraction of a multiple of 0.125. For example 201/8 = 25.125 and 203/8 = 25.375 So in any case, this will always lead to a terminating decimal. Sufficient My Answer: B
_________________
press kudos, if you like the explanation, appreciate the effort or encourage people to respond.
Download the Ultimate SC Flashcards
|
|
|
|
|
|
Intern
Joined: 31 Aug 2011
Posts: 1
Followers: 0
Kudos [?]:
0
[0], given: 3
|
Re: A terminating decimal is defined as a decimal that has a [#permalink]
24 Apr 2012, 04:20
Found this helpful explanation on Mgmat site. Author- Emily Sledge This rule took a while for me to internalize. It's tough to picture a decimal terminating when the denominator is so huge, such as DWG's example of 43/256. I found it helped me to think about the basic patterns: 1/2^1 = 0.5 1/2^2 = 0.25 1/2^3 = 0.125 1/2^4 = 0.0625 1/2^5 = 0.03125 1/2^6 = 0.015625 1/2^7 = 0.0078125 1/5^1 = 0.2 1/5^2 = 0.04 1/5^3 = 0.008 1/5^4 = 0.0016 1/5^5 = 0.00032 1/5^6 = 0.000064 1/5^7 = 0.0000128 Every one of these terminates, and the pattern indicates that would continue to be true for higher powers. The number of decimal places increases along with the powers of 2 or 5, but the number of decimal places will always be finite. In contrast, any factors other than 2 or 5 in the denominator can quickly be shown to be non-terminating, even for the most basic case (exponent of 1). Higher powers would be even messier: 1/3 = 0.33333(3 repeating) 1/6 = 0.16666(6 repeating) 1/7 = 0.142857(142857 repeating) 1/9 = 0.11111(1 repeating)
|
|
|
|
|
|
|
Re: A terminating decimal is defined as a decimal that has a
[#permalink]
24 Apr 2012, 04:20
|
|
|
|
|
|
|
|
|
|
|