Author 
Message 
TAGS:

Hide Tags

Intern
Joined: 19 Dec 2009
Posts: 8

If k is a positive integer and the tens digit of k+5 is 4, what is the
[#permalink]
Show Tags
Updated on: 27 Jul 2015, 08:48
Question Stats:
63% (01:49) correct 37% (01:55) wrong based on 735 sessions
HideShow timer Statistics
If k is a positive integer and the tens digit of k+5 is 4, what is the tens digit of k? (1) k > 35 (2) The units digit of k is greater than 5 Does it mean it can be: 36, 37 ... 44. from (1) statement and 36, 37, 38 and 39 from the (2) statement. and k is 3?
Official Answer and Stats are available only to registered users. Register/ Login.
Originally posted by bekbek on 06 Jan 2010, 22:18.
Last edited by Bunuel on 27 Jul 2015, 08:48, edited 1 time in total.
Renamed the topic, edited the question and added the OA.




Math Expert
Joined: 02 Sep 2009
Posts: 50007

Re: Ten's digit + 5 (GMATPrep q29)
[#permalink]
Show Tags
12 Sep 2010, 21:31
If k is a positive integer and the tens digit of k+5 is 4, what is the tens digit of k? Translate the stem: "the tens digit of k+5 is 4" > \(40\leq{k+5}\leq{49}\) > \(35\leq{k}\leq{44}\) > so the tens digit of \(k\) could be 3 or 4. Side note: strictly speaking \(k\) could be more than two digit number (for example 3digit \(x40\leq{k+5}\leq{x49}\) ), though as we are interested only in units and tens digit then this wouldn't change anything and we can neglect other digits. (1) k > 35 > just tells us that \(k\neq{35}\), so we have \(35<{k}\leq{44}\) > the tens digit of \(k\) could still be 3 or 4. Not sufficient. (2) The units digit of k is greater than 5 > \(k\) could only be 36, 37, 38, 39 > so the tens digit of \(k\) is 3. Sufficient. Answer: B.
_________________
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: 06 Apr 2010
Posts: 117

Re: Ten's digit + 5 (GMATPrep q29)
[#permalink]
Show Tags
30 Aug 2010, 09:24
alienfluid wrote: I can't seem to understand the question  how can a digit + 5 = 4? Are we talking about rounding numbers here? Can someone please explain? Hi, It's been asked about tens digit of K+5=4 hence its possible to have 4 as answer.... Answer should be B. My explanation for the answer as follows; 1. K>35 Stmt one satisfies many numbers starting from 36 till 44 where tens digit of k+5 is 4 (E.g. 36+5=41, 37+5=42....41+5=46). Here tens digit of K has two options either 3 or 4 hence can't answer uniqure number K. 2. Unit Digit of K is >5 For this we have only 4 options available which satisfies tens digit of k+5=4 condition. Numbers are 36, 37, 38 and 39. All these 4 numbers have only one unique number as tens digit i.e. 3 Hence we got our answer. Hence B is suff to answer the question. If you like explanation, consider for kudos....




Manager
Joined: 04 Feb 2007
Posts: 81

Re: If k is a positive integer and the tens digit of k+5 is 4, what is the
[#permalink]
Show Tags
07 Jan 2010, 00:05
bekbek wrote: Could anyone help what the question asks? Thanks.
If k is a positive integer and the tens digit of k+5 is 4, what is the tens digit of k?
1) k>35 2) The units digit of k is greater than 5.
OA is "B"
Does it mean it can be: 36, 37 ... 44. from (1) statement and 36, 37, 38 and 39 from the (2) statement. and k is 3? yes. That is correct. k can be any sized integer from 2 digit or more (it has to be at least 2 digits since the stimulus says it has a tens digit) lets consider that k is 3 digits: abcFrom the stimulus, in order for the tens digit of k+5 to equal 4: a35 < k < a45 here we see that the value of a doesn't matter so we only need to consider 2 digit numbers for k. so 35<k<45. 1) this is redundant from the information in the stimulus. INSUFF. 2) the units digit of k can be greater than 5 only when the tens digit is 3. SUFF.
_________________
If you like my post, a kudos is always appreciated



Manager
Joined: 17 Mar 2010
Posts: 145

Re: Ten's digit + 5 (GMATPrep q29)
[#permalink]
Show Tags
31 Aug 2010, 04:28
Question is not telling digit + 5 it is telling number + 5



Joined: 31 Dec 1969
Location: Russian Federation
Concentration: Entrepreneurship, International Business
GMAT 3: 740 Q40 V50 GMAT 4: 700 Q48 V38 GMAT 5: 710 Q45 V41 GMAT 6: 680 Q47 V36 GMAT 9: 740 Q49 V42 GMAT 11: 500 Q47 V33 GMAT 14: 760 Q49 V44
WE: Supply Chain Management (Energy and Utilities)

Re: Ten's digit + 5 (GMATPrep q29)
[#permalink]
Show Tags
01 Sep 2010, 15:08
Question stem says 40 <= k+5 <= 49, thus 35 <= k <= 44 Statement 1 says k > 35, thus 36 <= k <= 44. Tens digit could be 3 or 4, insufficient Taking into account the range of k provided in the question stem, statement 2 says that 36 <= k <= 39. Units digit must be 3, sufficient Answer B



Manager
Joined: 27 Mar 2010
Posts: 94

Re: Ten's digit + 5 (GMATPrep q29)
[#permalink]
Show Tags
12 Sep 2010, 18:11
alienfluid wrote: I can't seem to understand the question  how can a digit + 5 = 4? Are we talking about rounding numbers here? Can someone please explain? I solved it this way: Stmt1: Now the possible values satisfying this statement and question statement are: where, nos in bold represtents K. 36+5=41 37+5=42 38+5=43 ' ' ' till 44+5=49 But since there are are two answers for ten's Digit of K ie 3 and 4, stmt 1 is NS. Now taking stmt2 alone we can say that all the values where K's Ten's digits is 3 qualifies the statement condition, hence it is sufficient alone.All other values with K's Ten's digits as 4 will not qualify because in that case the 2nd stmt condition that K's unit digit is greater than 5 is not met. Hope it is clear!!!



Manager
Joined: 20 Jul 2010
Posts: 216

Re: Ten's digit + 5 (GMATPrep q29)
[#permalink]
Show Tags
13 Sep 2010, 06:23
I had interpreted the question as tenth digit of K when added by 5 gives 4. So tenth digit can be 9. Did anyone else interpret like this? Confusion is if 5 is added to number or tens digit
_________________
If you like my post, consider giving me some KUDOS !!!!! Like you I need them



Intern
Joined: 23 Jun 2010
Posts: 31

Re: Ten's digit + 5 (GMATPrep q29)
[#permalink]
Show Tags
26 Feb 2011, 15:25
udaymathapati wrote: alienfluid wrote: I can't seem to understand the question  how can a digit + 5 = 4? Are we talking about rounding numbers here? Can someone please explain? Hi, It's been asked about tens digit of K+5=4 hence its possible to have 4 as answer.... Answer should be B. My explanation for the answer as follows; 1. K>35 Stmt one satisfies many numbers starting from 36 till 44 where tens digit of k+5 is 4 (E.g. 36+5=41, 37+5=42....41+5=46). Here tens digit of K has two options either 3 or 4 hence can't answer uniqure number K. 2. Unit Digit of K is >5 For this we have only 4 options available which satisfies tens digit of k+5=4 condition. Numbers are 36, 37, 38 and 39. All these 4 numbers have only one unique number as tens digit i.e. 3 Hence we got our answer. Hence B is suff to answer the question. If you like explanation, consider for kudos.... I agree. The way the question is worded is misleading. Initially even I took it to be the tens digit of a number + 5 = 4 i.e. if a two digit number was say TU then T+5 =4. It made no sense. So I decided that it was one of those badly worded questions and took it to be k + 5 instead of T + 5. Once I got that correct, the question seemed pretty straight forward from there on... The trap here is that the question doesn't ask for the number k, rather asks what is the tens digit i.e. T. Thus B is sufficient.
_________________
DK  If you like what you read then give a Kudos! Diagnostic Test: 620 The past is a guidepost, not a hitching post. 



Manager
Status: Pushing Hard
Affiliations: GNGO2, SSCRB
Joined: 30 Sep 2012
Posts: 80
Location: India
Concentration: Finance, Entrepreneurship
GPA: 3.33
WE: Analyst (Health Care)

If k is a positive integer and the tens digit of k+5 is 4, what
[#permalink]
Show Tags
01 May 2013, 11:13
getzgetzu wrote: If k is a positive integer and tens digit of k+5 is 4, what is the tens digit of k?
1. k>35 2. The units digit of k is greater than 5. Hi, For me the answer for this DS is E ...... but different guys gave different answers for this, Can Elaborate & discuss, this Pls.
_________________
If you don’t make mistakes, you’re not working hard. And Now that’s a Huge mistake.



Math Expert
Joined: 02 Sep 2009
Posts: 50007

Re: If k is a positive integer and the tens digit of k+5 is 4, w
[#permalink]
Show Tags
02 May 2013, 02:56



Senior Manager
Joined: 21 Jan 2010
Posts: 278

Re: If k is a positive integer and the tens digit of k+5 is 4
[#permalink]
Show Tags
06 May 2013, 13:06
If k is a positive integer and the tens digit of k+5 is 4, what is the tens digit of k?
(1) k > 35 (2) The units digit of k is greater than 5
1) K > 35 . It can be 36,37,.....40,41.....etc. In case K< 40 than the answer is 3. If K>=40 and K <45 than the answer is 4. Insufficient.
2)Units digit is greater than 5. In this scenario, the integer has to be less than equal to 40. Therefore tens digit is 3. Hence B.



Intern
Joined: 20 Jan 2013
Posts: 43
Location: India
Concentration: Finance, Entrepreneurship
GPA: 3.42

Re: If k is a positive integer and the tens digit of k+5 is 4, what is the
[#permalink]
Show Tags
29 Jul 2015, 23:05
bekbek wrote: If k is a positive integer and the tens digit of k+5 is 4, what is the tens digit of k? (1) k > 35 (2) The units digit of k is greater than 5 Does it mean it can be: 36, 37 ... 44. from (1) statement and 36, 37, 38 and 39 from the (2) statement. and k is 3? We need to find the tens digit of k. (1).... k could be any no in range (36  44).. Tens digit can be 3 or 4.. Insufficient.. (2).... k can only be (3639).. Tens digit can be 3 only.. Sufficient..
_________________
Best GMAT Resources downloads http://gmatclub.com/forum/collectionofthebestgmatresources167295.html#p1329720
May we all emerge victorious



BSchool Thread Master
Joined: 13 Jul 2015
Posts: 69
Location: Singapore
WE: Operations (Investment Banking)

Re: If k is a positive integer and the tens digit of k+5 is 4
[#permalink]
Show Tags
31 Jul 2015, 03:02
bekbek wrote: If k is a positive integer and the tens digit of k+5 is 4, what is the tens digit of k? (1) k > 35 (2) The units digit of k is greater than 5 Does it mean it can be: 36, 37 ... 44. from (1) statement and 36, 37, 38 and 39 from the (2) statement. and k is 3? Hi Bekbek, i'm new here. How do you know how to classify whether this questions is 700 level or not? because it seems quite straightforward as compared to the other 700 level questions.



Math Expert
Joined: 02 Sep 2009
Posts: 50007

Re: If k is a positive integer and the tens digit of k+5 is 4
[#permalink]
Show Tags
16 Aug 2015, 10:33



BSchool Thread Master
Joined: 13 Jul 2015
Posts: 69
Location: Singapore
WE: Operations (Investment Banking)

Re: If k is a positive integer and the tens digit of k+5 is 4
[#permalink]
Show Tags
16 Aug 2015, 20:51
Bunuel wrote: SamuelWitwicky wrote: bekbek wrote: If k is a positive integer and the tens digit of k+5 is 4, what is the tens digit of k? (1) k > 35 (2) The units digit of k is greater than 5 Does it mean it can be: 36, 37 ... 44. from (1) statement and 36, 37, 38 and 39 from the (2) statement. and k is 3? Hi Bekbek, i'm new here. How do you know how to classify whether this questions is 700 level or not? because it seems quite straightforward as compared to the other 700 level questions. The system itself classifies a question based on users attempts shown in stats. oh wow! ok thanks a lot for answering my questions!



NonHuman User
Joined: 09 Sep 2013
Posts: 8496

Re: If k is a positive integer and the tens digit of k+5 is 4
[#permalink]
Show Tags
26 Jan 2018, 11:35
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




Re: If k is a positive integer and the tens digit of k+5 is 4 &nbs
[#permalink]
26 Jan 2018, 11:35






