|
Author |
Message |
|
TAGS:
|
|
|
Senior Manager
Joined: 12 Mar 2009
Posts: 318
Followers: 1
Kudos [?]:
13
[0], given: 1
|
Does the decimal equivalent of P/Q, where P and Q are [#permalink]
23 Jan 2010, 00:37
Question Stats:
86% (01:23) correct
13% (00:13) wrong based on 3 sessions
Does the decimal equivalent of P/Q, where P and Q are positive integers, contain only a finite number of nonzero digits? (1) P>Q (2) Q=8 Please explain
Last edited by Bunuel on 26 Jan 2012, 03:39, edited 1 time in total.
Edited the OA, it must be B not E
|
|
|
|
|
|
|
GMAT Club team member
Joined: 02 Sep 2009
Posts: 11534
Followers: 1795
Kudos [?]:
9560
[1] , given: 826
|
1
This post received KUDOS
vaivish1723 wrote: 26 Does the decimal equivalent of P/Q, where P and Q are positive integers, contain only a finite number of nonzero digits? (1) P>Q (2) Q=8 Please explain Oa is 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*5^2. Fraction \frac{3}{30} is also a terminating decimal, as \frac{3}{30}=\frac{1}{10} and denominator 10=2*5. Question: Does the decimal equivalent of P/Q, where P and Q are positive integers, contain only a finite number of nonzero digits? According to the above we must determine whether the denominator (after reducing the fraction, if possible) contains only the 2-s and/or 5-s as the prime factors. (1) P>Q, clearly insufficient. (2) Q=8=2^3, hence denominator has only 2 as prime factor. Fraction P/Q will be terminated decimal. Sufficient. Answer: B.
_________________
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
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!!!
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!!!
 What are GMAT Club Tests? 25 extra-hard Quant Tests
Find out what's new at GMAT Club - latest features and updates
|
|
|
|
|
|
Manager
Joined: 26 Nov 2009
Posts: 180
Followers: 3
Kudos [?]:
49
[0], given: 5
|
why am I seeing all the questions with wrong OA today or atleast it seemed to be  I too got the ans as B
|
|
|
|
|
|
CEO
Status: Nothing comes easy: neither do I want.
Joined: 12 Oct 2009
Posts: 2758
Location: Malaysia
Concentration: Marketing, Entrepreneurship
GMAT 1: 670 Q49 V31 GMAT 2: 710 Q50 V35
Followers: 123
Kudos [?]:
634
[0], given: 221
|
|
|
|
|
|
|
Senior Manager
Joined: 24 Jul 2009
Posts: 301
Followers: 2
Kudos [?]:
51
[0], given: 0
|
Bunuel wrote: vaivish1723 wrote: 26 Does the decimal equivalent of P/Q, where P and Q are positive integers, contain only a finite number of nonzero digits? (1) P>Q (2) Q=8 Please explain Oa is 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*5^2. Fraction \frac{3}{30} is also a terminating decimal, as \frac{3}{30}=\frac{1}{10} and denominator 10=2*5. Question: Does the decimal equivalent of P/Q, where P and Q are positive integers, contain only a finite number of nonzero digits? According to the above we must determine whether the denominator (after reducing the fraction, if possible) contains only the 2-s and/or 5-s as the prime factors. (1) P>Q, clearly insufficient. (2) Q=8=2^3, hence denominator has only 2 as prime factor. Fraction P/Q will be terminated decimal. Sufficient. Answer: B. (OA must be wrong) Hello Bunuel How can we say that the fraction given is a "reduced fraction". Because if it's not than 70/8 is a non-terminating value.
|
|
|
|
|
|
GMAT Club team member
Joined: 02 Sep 2009
Posts: 11534
Followers: 1795
Kudos [?]:
9560
[1] , given: 826
|
1
This post received KUDOS
nverma wrote: Hello Bunuel
How can we say that the fraction given is a "reduced fraction". Because if it's not than 70/8 is a non-terminating value. Denominator already has only 2-s so in this case it's 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 the 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. Hope it's clear.
_________________
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
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!!!
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!!!
 What are GMAT Club Tests? 25 extra-hard Quant Tests
Find out what's new at GMAT Club - latest features and updates
|
|
|
|
|
|
Manager
Joined: 10 Aug 2009
Posts: 125
Followers: 2
Kudos [?]:
11
[0], given: 13
|
Bunuel please excuse the stupid question but I'm quite weak in these types of questions.
* Does the rule basically say that any integer divided by either 2, 5, a multiple of either, or a product of these multiples will have a finite amount of decimals?
So any integer divided by any multiple of 5 will have a finite amount of decimals, etc.?
* And another basic question: 0 is neither positive nor negative right?
* I also don't completely understand what to do when we don't know whether the fraction is reduced to its lowest form. Can we still apply the same rule?
|
|
|
|
|
|
GMAT Club team member
Joined: 02 Sep 2009
Posts: 11534
Followers: 1795
Kudos [?]:
9560
[1] , given: 826
|
1
This post received KUDOS
nickk wrote: Bunuel please excuse the stupid question but I'm quite weak in these types of questions.
1.Does the rule basically say that any integer divided by either 2, 5, a multiple of either, or a product of these multiples will have a finite amount of decimals?
2. So any integer divided by any multiple of 5 will have a finite amount of decimals, etc.?
3. And another basic question: 0 is neither positive nor negative right?
4. I also don't completely understand what to do when we don't know whether the fraction is reduced to its lowest form. Can we still apply the same rule?
1. Not multiples but when denominator has only 2 and/or 5 in any integer power; 2. No, multiples of 5 are 5, 10, 15, 20, 25, 30, ... 1/30 won't be terminating as there is 3 in denominator. Maybe you meant 5 in any power? Then yes; 3. Yes, (though it's even); 4. If fraction has only 2 or/and 5 in denominator then it does not matter whether it's reduced. If there is some other integer in denominator we need reducing to see whether it can be cancelled.
_________________
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
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!!!
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!!!
 What are GMAT Club Tests? 25 extra-hard Quant Tests
Find out what's new at GMAT Club - latest features and updates
|
|
|
|
|
|
Manager
Joined: 10 Aug 2009
Posts: 125
Followers: 2
Kudos [?]:
11
[0], given: 13
|
Thanks! that explains everything
|
|
|
|
|
|
Manager
Joined: 20 Nov 2010
Posts: 232
Followers: 3
Kudos [?]:
4
[0], given: 38
|
|
|
|
|
|
|
Intern
Joined: 26 May 2011
Posts: 22
Location: United States
Followers: 0
Kudos [?]:
56
[1] , given: 0
|
1
This post received KUDOS
How to know these properties before, some book/site has these properties covered thoroughly.
|
|
|
|
|
|
Math Forum Moderator
Joined: 20 Dec 2010
Posts: 2100
Followers: 108
Kudos [?]:
655
[1] , given: 376
|
1
This post received KUDOS
arnoorichenna wrote: How to know these properties before, some book/site has these properties covered thoroughly. gmat-math-book-87417.htmlMGMAT Strategy Guides 4th Edition OG12, OG Quantitative Review 2 Nothing else is required beyond these for GMAT related quantitative concepts.
_________________
~fluke
Find out what's new at GMAT Club - latest features and updates
|
|
|
|
|
|
Manager
Status: Long way to go
Joined: 21 Aug 2010
Posts: 97
Location: United States
Followers: 1
Kudos [?]:
40
[0], given: 29
|
It is a repeat soln is explained in 700-question-94641.html
_________________
-------------------------------------
|
|
|
|
|
|
Director
Status: GMAT Learner
Joined: 14 Jul 2010
Posts: 672
Followers: 21
Kudos [?]:
108
[0], given: 31
|
Re: Does the decimal equivalent of P/Q, where P and Q are [#permalink]
26 Jan 2012, 03:15
|
|
|
|
|
|
|
Re: Does the decimal equivalent of P/Q, where P and Q are
[#permalink]
26 Jan 2012, 03:15
|
|
|
|
|
|
|
|
|
Similar topics |
Author |
Replies |
Last post |
|
Similar Topics:
|
|
|
|
Does the decimal equivalent of P/Q, where P and Q are
|
ricokevin |
6 |
26 Apr 2007, 07:25 |
|
|
|
Does the decimal equivalent of P/Q, where P and Q are
|
sidbidus |
4 |
26 Oct 2007, 23:34 |
|
|
|
Does the decimal equivalent of P/Q, where P and Q are
|
rags |
7 |
31 Oct 2007, 12:08 |
|
1
|
|
26 Does the decimal equivalent of P/Q, where P and Q are
|
redmouse |
6 |
22 May 2008, 20:39 |
|
|
|
Does the decimal equivalent of P/Q, where P and Q are
|
puma |
4 |
07 Jun 2008, 11:47 |
|
|
|
|
|
|