Author 
Message 
TAGS:

Hide Tags

Math Expert
Joined: 02 Sep 2009
Posts: 45222

How many integers n are there such that 1< 5n +5 < 25? [#permalink]
Show Tags
24 Sep 2012, 05:04
5
This post received KUDOS
Expert's post
6
This post was BOOKMARKED
Question Stats:
65% (00:37) correct 35% (00:36) wrong based on 1343 sessions
HideShow timer Statistics



Math Expert
Joined: 02 Sep 2009
Posts: 45222

Re: How many integers n are there such that 1< 5n +5 < 25? [#permalink]
Show Tags
24 Sep 2012, 05:04
4
This post received KUDOS
Expert's post
3
This post was BOOKMARKED



Senior Manager
Joined: 24 Aug 2009
Posts: 482
Schools: Harvard, Columbia, Stern, Booth, LSB,

Re: How many integers n are there such that 1< 5n +5 < 25? [#permalink]
Show Tags
24 Sep 2012, 05:15
1
This post received KUDOS
1< 5n +5 < 25 > 4<5n<20 > .8<n<4 Four integers are possible Answer B
_________________
If you like my Question/Explanation or the contribution, Kindly appreciate by pressing KUDOS. Kudos always maximizes GMATCLUB worth Game Theory
If you have any question regarding my post, kindly pm me or else I won't be able to reply



Manager
Joined: 12 Mar 2012
Posts: 146
Location: India
Concentration: Technology, General Management
GMAT Date: 07232012
WE: Programming (Telecommunications)

Re: How many integers n are there such that 1< 5n +5 < 25? [#permalink]
Show Tags
24 Sep 2012, 08:43
2
This post received KUDOS
Bunuel wrote: How many integers n are there such that 1< 5n +5 < 25?
(A) Five (B) Four (C) Three (D) Two (E) One
expression can be split into two equations: 1 < 5n + 5 ==> 5n > 4 ==> n > 0.8 5n + 5 < 25 ==> 5n < 20 ==> n < 4 now between 0.8 and 4(excluding) , there exist 4 integers, viz. 0, 1, 2, 3 hence B
_________________
FOCUS..this is all I need!
KuDo!



Math Expert
Joined: 02 Sep 2009
Posts: 45222

Re: How many integers n are there such that 1< 5n +5 < 25? [#permalink]
Show Tags
28 Sep 2012, 04:55



Senior Manager
Joined: 13 Aug 2012
Posts: 443
Concentration: Marketing, Finance
GPA: 3.23

Re: How many integers n are there such that 1< 5n +5 < 25? [#permalink]
Show Tags
10 Dec 2012, 04:23
\(1 < 5n +5 < 25\) \(1  5 < 5n + 5  5 < 25 5\) \(4 < 5n < 20\) \(4/5 < n < 4\) <===(1)=4/5 =(0)=(1)=(2)=(3)=(4)==> xaxisAnswer: B
_________________
Impossible is nothing to God.



Intern
Joined: 12 Nov 2012
Posts: 5

Re: How many integers n are there such that 1< 5n +5 < 25? [#permalink]
Show Tags
11 Dec 2012, 04:14
is it correct?
5*1+5=10 5*2+5=15 5*3+5=20 5*4+5=25 >n=4



Math Expert
Joined: 02 Sep 2009
Posts: 45222

Re: How many integers n are there such that 1< 5n +5 < 25? [#permalink]
Show Tags
11 Dec 2012, 04:56



Intern
Joined: 06 Jun 2013
Posts: 7

Re: How many integers n are there such that 1< 5n +5 < 25? [#permalink]
Show Tags
24 Jun 2013, 05:06
Bunuel wrote: SOLUTION
How many integers n are there such that 1< 5n +5 < 25?
(A) Five (B) Four (C) Three (D) Two (E) One
\(1< 5n +5 < 25\) > subtract 5 from each part: \(4<5n<20\) > divide by 5 each part: \(\frac{4}{5}<n<4\). In this range there are 4 integers: 0, 1, 2, and 3.
Answer: B. why is it not 1, 0, 1, 2, 3 ?



Math Expert
Joined: 02 Sep 2009
Posts: 45222

Re: How many integers n are there such that 1< 5n +5 < 25? [#permalink]
Show Tags
24 Jun 2013, 05:12
Rs1991 wrote: Bunuel wrote: SOLUTION
How many integers n are there such that 1< 5n +5 < 25?
(A) Five (B) Four (C) Three (D) Two (E) One
\(1< 5n +5 < 25\) > subtract 5 from each part: \(4<5n<20\) > divide by 5 each part: \(\frac{4}{5}<n<4\). In this range there are 4 integers: 0, 1, 2, and 3.
Answer: B. why is it not 1, 0, 1, 2, 3 ? Because 1 is LESS than 4/5, and n must be more than 4/5.
_________________
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? Extrahard Quant Tests with Brilliant Analytics



Intern
Joined: 06 Jan 2013
Posts: 11
Location: United States
Concentration: Finance, Economics
GMAT Date: 11152013
GPA: 3.5
WE: Education (Education)

Re: How many integers n are there such that 1< 5n +5 < 25? [#permalink]
Show Tags
05 Sep 2013, 23:18
1
This post received KUDOS
A table showing values of 5n+1 for various values of n. Just need to note the constraint that 1<5n+5<25 (valid values are in green, invalid in red) and count how many valid numbers there are for n.
Attachments
Table.png [ 2.57 KiB  Viewed 17642 times ]



Manager
Joined: 07 Apr 2014
Posts: 119

Re: How many integers n are there such that 1< 5n +5 < 25? [#permalink]
Show Tags
10 Sep 2014, 09:28
Bunuel wrote: How many integers n are there such that 1< 5n +5 < 25? (A) Five (B) Four (C) Three (D) Two (E) One Practice Questions Question: 50 Page: 158 Difficulty: 600 1< 5n +5 < 25 4<5n<20 so n can take 0,1,2,3, totally 4 integers..



Intern
Joined: 17 Jun 2015
Posts: 12
GPA: 3.35

Re: How many integers n are there such that 1< 5n +5 < 25? [#permalink]
Show Tags
11 Jul 2015, 00:22
Bunuel wrote: How many integers n are there such that 1< 5n +5 < 25? (A) Five (B) Four (C) Three (D) Two (E) One Practice Questions Question: 50 Page: 158 Difficulty: 600 i count only 1,2,and 3 for that reason i choose 3 integer solution: must be count from 0 so, 0,1,2,and 3 so answer: the range of integer 4



Director
Joined: 24 Nov 2015
Posts: 564
Location: United States (LA)

Re: How many integers n are there such that 1< 5n +5 < 25? [#permalink]
Show Tags
08 May 2016, 14:34
The inequality given is 1 < 5n+5 < 25 it can further reduced to 4 < 5n < 20 finally 4/5 < n < 4 So can only take 5 integer values i.e. 0,1,2,3 Correct answer  B



Target Test Prep Representative
Status: Head GMAT Instructor
Affiliations: Target Test Prep
Joined: 04 Mar 2011
Posts: 2442

Re: How many integers n are there such that 1< 5n +5 < 25? [#permalink]
Show Tags
09 May 2016, 10:57
Bunuel wrote: How many integers n are there such that 1< 5n +5 < 25? (A) Five (B) Four (C) Three (D) Two (E) One Practice Questions Question: 50 Page: 158 Difficulty: 600 Solution: 1< 5n + 5 < 25 is a compound inequality. Compound inequalities often need to be manipulated, and we can use the rules of algebra that we already know, to do this. Just as with equations, whatever we do to one part of a compound inequality, we must do to all parts of the compound inequality. Let’s first isolate n within the inequality. 1< 5n + 5 < 25 We first subtract 5 from all three parts of the inequality, and we obtain: 4 < 5n < 20 Next, we divide both sides of the inequality by 5 and we get: 4/5 < n < 4 The integers that are greater than 4/5 and less than 4 are 0, 1, 2, and 3. Thus, there are 4 integers that satisfy the inequality 1 < 5n + 5 < 25. The answer is B.
_________________
Jeffery Miller
Head of GMAT Instruction
GMAT Quant SelfStudy Course
500+ lessons 3000+ practice problems 800+ HD solutions



Intern
Joined: 18 Apr 2016
Posts: 9

Re: How many integers n are there such that 1< 5n +5 < 25? [#permalink]
Show Tags
09 Jun 2016, 07:10
Bunuel wrote: fabrizio1983 wrote: is it correct?
5*1+5=10 5*2+5=15 5*3+5=20 5*4+5=25 >n=4 No, that's not correct. n cannot be 4, since 5*4+5=25 and we are told that it must be less than 25. 1< 5n +5 < 25 n=0 > 5n +5=5; n=1 > 5n +5=10; n=2 > 5n +5=15; n=3 > 5n +5=20. Thus n can take 4 values: 0, 1, 2, or 3. Check here: howmanyintegersnaretheresuchthat15n139474.html#p1124669We are also told n is greater than 1, than how can we take 0 and 1 in the answer choice???



Math Expert
Joined: 02 Sep 2009
Posts: 45222

Re: How many integers n are there such that 1< 5n +5 < 25? [#permalink]
Show Tags
09 Jun 2016, 07:18
Lucky_Rish wrote: Bunuel wrote: fabrizio1983 wrote: is it correct?
5*1+5=10 5*2+5=15 5*3+5=20 5*4+5=25 >n=4 No, that's not correct. n cannot be 4, since 5*4+5=25 and we are told that it must be less than 25. 1< 5n +5 < 25 n=0 > 5n +5=5; n=1 > 5n +5=10; n=2 > 5n +5=15; n=3 > 5n +5=20. Thus n can take 4 values: 0, 1, 2, or 3. Check here: howmanyintegersnaretheresuchthat15n139474.html#p1124669We are also told n is greater than 1, than how can we take 0 and 1 in the answer choice??? We are not told that n is greater than 1. We are told that \(1< 5n +5 < 25\), which is the same as \(−\frac{4}{5} < n < 4\).
_________________
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? Extrahard Quant Tests with Brilliant Analytics



Manager
Joined: 12 Jun 2016
Posts: 221
Location: India
Concentration: Technology, Leadership
WE: Sales (Telecommunications)

Re: How many integers n are there such that 1< 5n +5 < 25? [#permalink]
Show Tags
11 Jun 2017, 22:39
Hi! To avoid getting into the trap of a ve number and fractions, we can do the following Given: \(1 < 5n+5<25\) ; Subtract throughout by 1 = \(0 < 5n+4 < 24\) > We need all positive integers which satisfies this equation. = \(4, 9, 14, 19\) are the possibilities Final answer = four
_________________
My Best is yet to come!



Manager
Joined: 02 Jan 2017
Posts: 81
Location: Pakistan
Concentration: Finance, Technology
GPA: 3.41
WE: Business Development (Accounting)

Re: How many integers n are there such that 1< 5n +5 < 25? [#permalink]
Show Tags
18 Dec 2017, 08:14
Should this question be for 600700 Difficulty range? I think it should be moved to 500600 range.



Intern
Joined: 17 Jul 2016
Posts: 35

Re: How many integers n are there such that 1< 5n +5 < 25? [#permalink]
Show Tags
18 Dec 2017, 09:12
the minimum n can be is 0. The maximum it can be is 3. So n can be anything from 0 to 3. It can be 0,1,2, or 3 for a total of 4 values.




Re: How many integers n are there such that 1< 5n +5 < 25?
[#permalink]
18 Dec 2017, 09:12



Go to page
1 2
Next
[ 22 posts ]



