Author 
Message 
TAGS:

Hide Tags

Intern
Joined: 02 Aug 2011
Posts: 9

If n is an integer and n^3 is between 1 and 100, inclusive, what is
[#permalink]
Show Tags
10 Aug 2011, 13:56
Question Stats:
58% (00:58) correct 42% (01:00) wrong based on 38 sessions
HideShow timer Statistics
If n is an integer and n^3 is between 1 and 100, inclusive, what is the value of n? (1) n = 2k+1, where k is an integer. (2) n is a prime number. This is an example question from Manhattan Gmat Numbers Properties guide 1. When I initially did the question, I chose statement 1. as sufficient on its own. Firstly, in the question stem you can narrow down the choices for n as being between 1 and 4. I then tested numbers in the equation in statement 1 and felt able to conclude that n was 3, as plugging any other integers higher than 1 for k made n>4. Statement 2 only allows me to narrow the choice down to 2 or 3 so its insufficient. BUT when i read through the answer explanation, they dismiss statement 1 as only telling us that n is odd, meaning it leaves us with a choice of 1 or 3, therefore, you'd need both statements to be able to conclude that n was 3. Could someone tell me where I went wrong? OPEN DISCUSSION OF THIS QUESTION IS HERE: https://gmatclub.com/forum/ifnisani ... 03171.html
Official Answer and Stats are available only to registered users. Register/ Login.





Manager
Status: CEO in training
Affiliations: ACCA
Joined: 20 Sep 2010
Posts: 67
Concentration: Entrepreneurship, Marketing

Re: If n is an integer and n^3 is between 1 and 100, inclusive, what is
[#permalink]
Show Tags
10 Aug 2011, 14:06
K can be zero and zero is an integer. Thus, I don't think statement 1 alone is sufficient.
_________________
http://gmatclub.com/forum/realbusinessschooladmissionsessaytopicshumor78619.html#p591652



Manager
Status: CEO in training
Affiliations: ACCA
Joined: 20 Sep 2010
Posts: 67
Concentration: Entrepreneurship, Marketing

Re: If n is an integer and n^3 is between 1 and 100, inclusive, what is
[#permalink]
Show Tags
10 Aug 2011, 14:08
k might also have been a negative integer but given that n^3 is between 1 and 100, this part of the number line is ruled out.
_________________
http://gmatclub.com/forum/realbusinessschooladmissionsessaytopicshumor78619.html#p591652



Intern
Joined: 02 Aug 2011
Posts: 9

Re: If n is an integer and n^3 is between 1 and 100, inclusive, what is
[#permalink]
Show Tags
10 Aug 2011, 14:22
schemer wrote: K can be zero and zero is an integer. Thus, I don't think statement 1 alone is sufficient. yes, it can be zero! that'll give me 1 as the answer. I guess I'm not out of the habit of think of integers as 1 and beyond. i don't think i'll forget the importance of the almighty zero from now on! thanks for the quick response.



Director
Joined: 03 May 2007
Posts: 829
Schools: University of Chicago, Wharton School

Re: If n is an integer and n^3 is between 1 and 100, inclusive, what is
[#permalink]
Show Tags
10 Aug 2011, 14:33
meshell wrote: If n is an integer and n^3 is between 1 and 100 inclusive, what is the value of n? (1) n= 2k +1, where k is an integer (2) n is a prime number. This is an example question from Manhattan Gmat Numbers Properties guide 1. When I initially did the question, I chose statement 1. as sufficient on its own. Firstly, in the question stem you can narrow down the choices for n as being between 1 and 4. I then tested numbers in the equation in statement 1 and felt able to conclude that n was 3, as plugging any other integers higher than 1 for k made n>4. Statement 2 only allows me to narrow the choice down to 2 or 3 so its insufficient. BUT when i read through the answer explanation, they dismiss statement 1 as only telling us that n is odd, meaning it leaves us with a choice of 1 or 3, therefore, you'd need both statements to be able to conclude that n was 3. Could someone tell me where I went wrong? If n is an integer and n^3 is between 1 and 100 inclusive, what is the value of n From the question n can be only be positive integers: either 1 or 2 or 3 or 4. (1) If n = 2k +1, where k is an integer: Here, k can only be 0 and 1 and n could be 1 or 3. not sufficient. (2) If n is a prime number, n could be 2 or 3. from 1 and 2, n is 3. So that's C.



Manager
Joined: 16 Feb 2011
Posts: 224

Re: If n is an integer and n^3 is between 1 and 100, inclusive, what is
[#permalink]
Show Tags
12 Aug 2011, 12:04
Fistail wrote: meshell wrote: If n is an integer and n^3 is between 1 and 100 inclusive, what is the value of n? (1) n= 2k +1, where k is an integer (2) n is a prime number. This is an example question from Manhattan Gmat Numbers Properties guide 1. When I initially did the question, I chose statement 1. as sufficient on its own. Firstly, in the question stem you can narrow down the choices for n as being between 1 and 4. I then tested numbers in the equation in statement 1 and felt able to conclude that n was 3, as plugging any other integers higher than 1 for k made n>4. Statement 2 only allows me to narrow the choice down to 2 or 3 so its insufficient. BUT when i read through the answer explanation, they dismiss statement 1 as only telling us that n is odd, meaning it leaves us with a choice of 1 or 3, therefore, you'd need both statements to be able to conclude that n was 3. Could someone tell me where I went wrong? If n is an integer and n^3 is between 1 and 100 inclusive, what is the value of n From the question n can be only be positive integers: either 1 or 2 or 3 or 4. (1) If n = 2k +1, where k is an integer: Here, k can only be 0 and 1 and n could be 1 or 3. not sufficient. (2) If n is a prime number, n could be 2 or 3. from 1 and 2, n is 3. So that's C. Can you pls help me understand why K will ONLY b "0" or "1"??



Manager
Joined: 28 May 2011
Posts: 170
Location: United States
Concentration: General Management, International Business
GPA: 3.6
WE: Project Management (Computer Software)

Re: If n is an integer and n^3 is between 1 and 100, inclusive, what is
[#permalink]
Show Tags
12 Aug 2011, 12:09
DeeptiM wrote: Can you pls help me understand why K will ONLY b "0" or "1"?? Because possible values of n = 1,2,3,4 (only there cubes will lie between 1 and 100) and if n = 2k+1 => k = 1 (n = 3), 0 (n=1)
_________________
 http://gmatclub.com/forum/aguidetotheofficialguide13forgmatreview134210.html 



Intern
Joined: 17 May 2009
Posts: 30
Location: United States
GPA: 3.62
WE: Corporate Finance (Manufacturing)

Re: If n is an integer and n^3 is between 1 and 100, inclusive, what is
[#permalink]
Show Tags
14 Aug 2011, 17:48
If n is an integer and n^3 is between 1 and 100 inclusive, what is the value of n? (1) n= 2k +1, where k is an integer (2) n is a prime number. 
[strike]n = 1, n^3 = 1[/strike] [strike]n = 0, n^3 = 0[/strike] n = 1, n^3 = 1 n = 2, n^3 = 8 n = 3, n^3 = 27 n = 4, n^3 = 64 [strike]n = 5, n^3 = 125[/strike] 1 <= n^3 <= 100, so 1 <= n <= 4. Rephrase the question stem: "n = 1, 2, 3, or 4. What is n?" Statement 1) "n is odd", so n could be 1 or 3. Insufficient. Statement 2) n is prime, so n could be 2 or 3. Insufficient. Combined) n is an odd prime number, so 3 is the only possibility. Sufficient.



Retired Thread Master
Status: How can I crack Verbal
Joined: 12 May 2011
Posts: 178
Location: India
Concentration: General Management, Finance
GPA: 3

Re: If n is an integer and n^3 is between 1 and 100, inclusive, what is
[#permalink]
Show Tags
15 Aug 2011, 09:09
c.. 1. n can be 1 or 3 (when k=0 and 1 repectively) 2.n can be 2,3
combine both stmnts,we have n=3



Intern
Joined: 05 Mar 2011
Posts: 7

Re: If n is an integer and n^3 is between 1 and 100, inclusive, what is
[#permalink]
Show Tags
17 Aug 2011, 17:00
Yup .Its C.
We should not miss considering K=0.



Director
Joined: 01 Feb 2011
Posts: 671

Re: If n is an integer and n^3 is between 1 and 100, inclusive, what is
[#permalink]
Show Tags
17 Aug 2011, 19:18
n is an integer
n^3 lies between 1 and 100.
=> n can only be positive integer and n can be 1 or 2 or 3 or 4
1. Not Sufficient
n is odd integer => n can be 1 or 3
2. Not sufficient
n is 2 or 3
Together,
Its sufficient , n =3.
Answer is C.



Manager
Joined: 16 Feb 2011
Posts: 224

Re: If n is an integer and n^3 is between 1 and 100, inclusive, what is
[#permalink]
Show Tags
17 Aug 2011, 19:56
anordinaryguy wrote: DeeptiM wrote: Can you pls help me understand why K will ONLY b "0" or "1"?? Because possible values of n = 1,2,3,4 (only there cubes will lie between 1 and 100) and if n = 2k+1 => k = 1 (n = 3), 0 (n=1) Ahh..revisited the ques n got to knw d mistake.. Thanks for the explanation..kudos to u!!



Director
Status: Prep started for the nth time
Joined: 29 Aug 2010
Posts: 560

Re: If n is an integer and n^3 is between 1 and 100, inclusive, what is
[#permalink]
Show Tags
19 Aug 2011, 21:47
+1 for C.
Agree with bodleyev's explanation. Kudos to him
Crick



Manager
Joined: 14 Mar 2011
Posts: 74

Re: If n is an integer and n^3 is between 1 and 100, inclusive, what is
[#permalink]
Show Tags
19 Aug 2011, 22:37
From Question n^3 is between 1 & 100 so n can not be negative now 1^3=1 2^3=8 3^3=27 4^=64 values greater than 4 ruled out 1. n = 2k+1, not sufficient to identify the answer 2. n= Prime number not sufficient to identify the answer
combining both k can be 0 or 1 as we are restricted to values of n=1, 2, 3 & 4 so 4 is also ruled out we are left with 1, 2 & 3 Now A natural number is called a prime number (or a prime) if it is bigger than one and has no divisors other than 1 and itself. So left with 2 & 3 now here k value becomes 1 so answer come to 3
So C is right Answer
Give Kudos if you understood it



Math Expert
Joined: 02 Sep 2009
Posts: 47983

Re: If n is an integer and n^3 is between 1 and 100, inclusive, what is
[#permalink]
Show Tags
13 Dec 2017, 23:44
If n is an integer and n^3 is between 1 and 100, inclusive, what is the value of n?n is an integer and \(n^3\) is between 1 and 100, inclusive, means that n could be 1, 2, 3 or 4 (but not 5 or more since 5^3 = 125 > 100). (1) n = 2k+1, where k is an integer > n is an odd number > n could be 1 or 3. Not sufficient. (2) n is a prime number > n could be 2 or 3. Not sufficient. (1)+(2) n could be only 3. Sufficient. Answer: C. OPEN DISCUSSION OF THIS QUESTION IS HERE: https://gmatclub.com/forum/ifnisani ... 03171.html
_________________
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




Re: If n is an integer and n^3 is between 1 and 100, inclusive, what is &nbs
[#permalink]
13 Dec 2017, 23:44






