GMAT Question of the Day - Daily to your Mailbox; hard ones only

It is currently 06 Dec 2019, 20:57

Close

GMAT Club Daily Prep

Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.

Customized
for You

we will pick new questions that match your level based on your Timer History

Track
Your Progress

every week, we’ll send you an estimated GMAT score based on your performance

Practice
Pays

we will pick new questions that match your level based on your Timer History

Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.

Close

Request Expert Reply

Confirm Cancel

For all positive integers m, [m]=3m when m is odd and [m]=(1/2)*m when

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
TAGS:

Hide Tags

Find Similar Topics 
Intern
Intern
avatar
Joined: 05 Sep 2010
Posts: 19
For all positive integers m, [m]=3m when m is odd and [m]=(1/2)*m when  [#permalink]

Show Tags

New post Updated on: 02 Jun 2019, 23:07
9
105
00:00
A
B
C
D
E

Difficulty:

  35% (medium)

Question Stats:

63% (01:10) correct 37% (01:09) wrong based on 1111 sessions

HideShow timer Statistics

For all positive integers m, [m] = 3m when m is odd and [m] = (1/2)*m when m is even. What is [9]*[6] equivalent to?

A. [81]
B. [54]
C. [37]
D. [27]
E. [18]

Originally posted by Guduna on 08 Sep 2010, 06:38.
Last edited by Bunuel on 02 Jun 2019, 23:07, edited 3 times in total.
Edited the question.
Most Helpful Expert Reply
Math Expert
User avatar
V
Joined: 02 Sep 2009
Posts: 59587
Re: For all positive integers m, [m]=3m when m is odd and [m]=(1/2)*m when  [#permalink]

Show Tags

New post 08 Sep 2010, 07:41
52
39
Guduna wrote:
For all positive integers m, m*= 3m when m is odd and m*=1/2 when m is even. Which of the following is equivalent to 9* x 6*
81
54
36
27
18


Pleas post the questions in their original form.

For all positive integers m, [m]=3m when m is odd and [m]=(1/2)*m when m is even. What is [9]*[6] equivalent to?

A. [81]
B. [54]
C. [37]
D. [27]
E. [18]

Notice that [] is just some function such that "[m]=3m when m is odd and [m]=(1/2)*m when m is even".

So, [m]=3m when m is odd, [m]=(1/2)*m when m is even.
As 9 is odd then [9] equals to 3*9=27;
As 6 is even then [6] equals to 1/2*6=3;

So [9]*[6]=27*3=81. Note that numbers in the answer choices are also in boxes, so we have: [m]=81. m could be 27 (in this case as 27 is odd [27]=3*27=81) OR 162 (in this case as 162 is even [162]=162/2=81) --> only [27] is in the answer choices.

Answer: D.

Similar question to practice: when-x-is-even-x-2-1-when-x-is-odd-2x-1-then-132059.html
_________________
Most Helpful Community Reply
SVP
SVP
User avatar
Status: The Best Or Nothing
Joined: 27 Dec 2012
Posts: 1727
Location: India
Concentration: General Management, Technology
WE: Information Technology (Computer Software)
Re: For all positive integers m, [m]=3m when m is odd and [m]=(1/2)*m when  [#permalink]

Show Tags

New post 19 Jun 2014, 04:51
12
1
[9] = 9 * 3 = 27

\([6] = \frac{6}{2} = 3\)

[9] * [6] = 27 * 3 = 81 ............. (1)

From all the given options, we require to calculate to get answer 81

A. [81] = 81 * 3 = 243 .... IGNORE


\(B. [54] = \frac{54}{2} = 27 ......... IGNORE\)


C. [37] = 37 * 3 = 111 ..... IGNORE


D. [27] = 27 * 3 = 81 ........... Matches with (1)


\(E. [18] = \frac{18}{2} = 9 ........... IGNORE\)

Answer = D
General Discussion
Intern
Intern
avatar
Joined: 05 Sep 2010
Posts: 19
Re: For all positive integers m, [m]=3m when m is odd and [m]=(1/2)*m when  [#permalink]

Show Tags

New post 08 Sep 2010, 08:01
2
Bunuel

Thank you so much I didn't look at the answers that they were also in squares..

Thanks
Manager
Manager
User avatar
Joined: 13 Jul 2010
Posts: 100
Re: For all positive integers m, [m]=3m when m is odd and [m]=(1/2)*m when  [#permalink]

Show Tags

New post 08 Dec 2010, 20:36
got answer D is explained above. Bunuel good point on the even number bracket as well for the function. Did not think of that.
Intern
Intern
avatar
Joined: 13 Jul 2010
Posts: 4
Re: For all positive integers m, [m]=3m when m is odd and [m]=(1/2)*m when  [#permalink]

Show Tags

New post 22 Nov 2011, 22:12
1
galaxyblue wrote:
[m] = 3m when m is odd
[m] = 1/2m when m is even
what is [9]x[6]?

A 81
B 54
C 36
D 27
E 18


9 is odd, 6 is even.

By the way this is set up, it should be 3*9*(1/2*6)

with that said, 27*3 should be A IMO
Intern
Intern
User avatar
Joined: 10 Oct 2011
Posts: 29
Concentration: Operations, Marketing
Schools: Broad (S)
GPA: 3.1
WE: Project Management (Non-Profit and Government)
Re: For all positive integers m, [m]=3m when m is odd and [m]=(1/2)*m when  [#permalink]

Show Tags

New post 23 Nov 2011, 06:46
1
rooster wrote:

9 is odd, 6 is even.

By the way this is set up, it should be 3*9*(1/2*6)

with that said, 27*3 should be A IMO



That is what I got, but it is not the answer.

I even set it up like: 9 = 3m, therefore m is 3 and 6 = 1/2 m, then m = 12. So 12 x 3 = 36. Still wrong.

So then I did 9x6 = [54] = 3m x 1/2m => 54 = 3/2m => solve for m, m=36
Manager
Manager
avatar
Joined: 30 Aug 2009
Posts: 217
Location: India
Concentration: General Management
Re: For all positive integers m, [m]=3m when m is odd and [m]=(1/2)*m when  [#permalink]

Show Tags

New post 10 Jan 2012, 07:59
4
1
Janealams wrote:
I have exam tomorrow. I will really appreciate if any of you can explain solution to this question. Thanks :)

Why should we not solve 9 and 6 individually?


when m is 9 (odd) then [m] = 3 * m = [9] = 27 and

m is 6 (even) then [m] =1/2m = [6] = (1/2)*6 = 3

so we get [9] * [6] = 27 *3 = 81

but answers are all in [] so 81 (odd and hence in 3m format) will be equal to [27]

[] used for box symbol used in q
Intern
Intern
avatar
Joined: 19 Aug 2011
Posts: 20
Concentration: Finance, Entrepreneurship
Re: For all positive integers m, [m]=3m when m is odd and [m]=(1/2)*m when  [#permalink]

Show Tags

New post 03 Apr 2012, 02:41
6
1
Pure deception. Got caught in the trap. :shock:
Manager
Manager
avatar
Status: I will not stop until i realise my goal which is my dream too
Joined: 25 Feb 2010
Posts: 158
Schools: Johnson '15
Re: For all positive integers m, [m]=3m when m is odd and [m]=(1/2)*m when  [#permalink]

Show Tags

New post 03 Apr 2012, 06:53
1
Bunuel wrote:
Guduna wrote:
For all positive integers m, m*= 3m when m is odd and m*=1/2 when m is even. Which of the following is equivalent to 9* x 6*
81
54
36
27
18


Pleas post the questions in their original form.

For all positive integers m, [m]=3m when m is odd and [m]=(1/2)*m when m is even. What is [9]*[6] equivalent to?

A. [81]
B. [54]
C. [37]
D. [27]
E. [18]

Note that [] is just some function such that "[m]=3m when m is odd and [m]=(1/2)*m when m is even".

So, [m]=3m when m is odd, [m]=(1/2)*m when m is even.
As 9 is odd then [9] equals to 3*9=27;
As 6 is even then [6] equals to 1/2*6=3;

So [9]*[6]=27*3=81. Note that numbers in the answer choices are also in boxes, so we have: [m]=81. m could be 27 (in this case as 27 is odd [27]=3*27=81) OR 162 (in this case as 162 is even [162]=162/2=81) --> only [27] is in the answer choices.

Answer: D.



i had selected A, but then realised my mistake....Buneal the god....wounderful explanation....
Intern
Intern
avatar
Joined: 04 Apr 2012
Posts: 2
Location: India
Re: For all positive integers m, [m]=3m when m is odd and [m]=(1/2)*m when  [#permalink]

Show Tags

New post 07 Apr 2012, 09:23
galaxyblue wrote:
rooster wrote:

9 is odd, 6 is even.

By the way this is set up, it should be 3*9*(1/2*6)

with that said, 27*3 should be A IMO



That is what I got, but it is not the answer.

I even set it up like: 9 = 3m, therefore m is 3 and 6 = 1/2 m, then m = 12. So 12 x 3 = 36. Still wrong.

So then I did 9x6 = [54] = 3m x 1/2m => 54 = 3/2m => solve for m, m=36



Going by the answer, they might have calculated this way [9][6] = [54] = 54/2 =27, but I would still go for option A.
Math Expert
User avatar
V
Joined: 02 Sep 2009
Posts: 59587
Re: For all positive integers m, [m]=3m when m is odd and [m]=(1/2)*m when  [#permalink]

Show Tags

New post 21 Jun 2013, 03:47
Intern
Intern
avatar
Joined: 10 Apr 2014
Posts: 29
Re: For all positive integers m, [m]=3m when m is odd and [m]=(1/2)*m when  [#permalink]

Show Tags

New post 13 Apr 2014, 02:32
AJ21 wrote:
For all positive integers m, m = 3m when m is odd and m = 1/2m when m is even. Which of the following is equivalent to 9 x 6

a.81
b.54
c.36
d.27
e.18

Thanks in advance


Hi,

9 x 6 = 3*9*6/2 = 27*3 = 81

So, from the given options the answer is A.

But as the official answer you have given is D, The options should have _ line under them.
If options are:

a.81
b.54
c.36
d.27
e.18

The answer would be D because 27= 3*27 = 81


------------------------------------
Kudos if the post helped :)
Manager
Manager
avatar
Joined: 15 Aug 2013
Posts: 227
Re: For all positive integers m, [m]=3m when m is odd and [m]=(1/2)*m when  [#permalink]

Show Tags

New post 13 Jun 2014, 19:13
Bunuel wrote:
Guduna wrote:
For all positive integers m, m*= 3m when m is odd and m*=1/2 when m is even. Which of the following is equivalent to 9* x 6*
81
54
36
27
18


Pleas post the questions in their original form.

For all positive integers m, [m]=3m when m is odd and [m]=(1/2)*m when m is even. What is [9]*[6] equivalent to?

A. [81]
B. [54]
C. [37]
D. [27]
E. [18]

Notice that [] is just some function such that "[m]=3m when m is odd and [m]=(1/2)*m when m is even".

So, [m]=3m when m is odd, [m]=(1/2)*m when m is even.
As 9 is odd then [9] equals to 3*9=27;
As 6 is even then [6] equals to 1/2*6=3;

So [9]*[6]=27*3=81. Note that numbers in the answer choices are also in boxes, so we have: [m]=81. m could be 27 (in this case as 27 is odd [27]=3*27=81) OR 162 (in this case as 162 is even [162]=162/2=81) --> only [27] is in the answer choices.

Answer: D.

Similar question to practice: when-x-is-even-x-2-1-when-x-is-odd-2x-1-then-132059.html


Hi Bunuel,

I'm a little confused by this question as a whole. I can easily follow your steps but the way I did/interpreted the problem is as follows:

[9] X [6] =>

[9]=3m
m=3

[6]=1/2m
m=12

Therefore: 12*3 = 36 since since both of the [m] functions were multiplied, the answer is also in a [36] (function form). Why is that wrong?

Thanks
Math Expert
User avatar
V
Joined: 02 Sep 2009
Posts: 59587
Re: For all positive integers m, [m]=3m when m is odd and [m]=(1/2)*m when  [#permalink]

Show Tags

New post 14 Jun 2014, 01:50
russ9 wrote:
Bunuel wrote:
Guduna wrote:
For all positive integers m, m*= 3m when m is odd and m*=1/2 when m is even. Which of the following is equivalent to 9* x 6*
81
54
36
27
18


Pleas post the questions in their original form.

For all positive integers m, [m]=3m when m is odd and [m]=(1/2)*m when m is even. What is [9]*[6] equivalent to?

A. [81]
B. [54]
C. [37]
D. [27]
E. [18]

Notice that [] is just some function such that "[m]=3m when m is odd and [m]=(1/2)*m when m is even".

So, [m]=3m when m is odd, [m]=(1/2)*m when m is even.
As 9 is odd then [9] equals to 3*9=27;
As 6 is even then [6] equals to 1/2*6=3;

So [9]*[6]=27*3=81. Note that numbers in the answer choices are also in boxes, so we have: [m]=81. m could be 27 (in this case as 27 is odd [27]=3*27=81) OR 162 (in this case as 162 is even [162]=162/2=81) --> only [27] is in the answer choices.

Answer: D.

Similar question to practice: when-x-is-even-x-2-1-when-x-is-odd-2x-1-then-132059.html


Hi Bunuel,

I'm a little confused by this question as a whole. I can easily follow your steps but the way I did/interpreted the problem is as follows:

[9] X [6] =>

[9]=3m
m=3

[6]=1/2m
m=12

Therefore: 12*3 = 36 since since both of the [m] functions were multiplied, the answer is also in a [36] (function form). Why is that wrong?

Thanks


[9] doe not equal to 3m.
[m] = 3m when m is odd. 9 is odd , hence [9] = 3*9 = 27.

The same way, [6] does not equal to 1/2*m.
[m]=(1/2)*m when m is even. 6 is even, hence [6] = 1/2*6 = 3.

Hope it's clear.
_________________
Intern
Intern
User avatar
Joined: 12 Aug 2014
Posts: 6
Location: Peru
GPA: 3.82
Re: For all positive integers m, [m]=3m when m is odd and [m]=(1/2)*m when  [#permalink]

Show Tags

New post 10 Dec 2014, 12:35
Bunuel wrote:
Guduna wrote:
For all positive integers m, m*= 3m when m is odd and m*=1/2 when m is even. Which of the following is equivalent to 9* x 6*
81
54
36
27
18


Pleas post the questions in their original form.

For all positive integers m, [m]=3m when m is odd and [m]=(1/2)*m when m is even. What is [9]*[6] equivalent to?

A. [81]
B. [54]
C. [37]
D. [27]
E. [18]

Notice that [] is just some function such that "[m]=3m when m is odd and [m]=(1/2)*m when m is even".

So, [m]=3m when m is odd, [m]=(1/2)*m when m is even.
As 9 is odd then [9] equals to 3*9=27;
As 6 is even then [6] equals to 1/2*6=3;

So [9]*[6]=27*3=81. Note that numbers in the answer choices are also in boxes, so we have: [m]=81. m could be 27 (in this case as 27 is odd [27]=3*27=81) OR 162 (in this case as 162 is even [162]=162/2=81) --> only [27] is in the answer choices.

Answer: D.

Similar question to practice: when-x-is-even-x-2-1-when-x-is-odd-2x-1-then-132059.html





Easy math but very tricky. Excelent explanation by Bunuel.
LBS Moderator
avatar
B
Joined: 13 Jan 2015
Posts: 94
Location: United Kingdom
Concentration: Other, General Management
Schools: LBS '19 (WL)
GMAT 1: 690 Q48 V36
Re: For all positive integers m, [m]=3m when m is odd and [m]=(1/2)*m when  [#permalink]

Show Tags

New post 24 Mar 2015, 05:11
Dang, I cross-checked this answer and I was thinking, the GMAT would surely test harder questions on this exam and as it was the second question, it would not be this easy..

Well, I got stung, lesson learned, pay as much attention to answer choices as to the question itself...
the dam box
Current Student
User avatar
D
Joined: 12 Aug 2015
Posts: 2548
Schools: Boston U '20 (M)
GRE 1: Q169 V154
GMAT ToolKit User
Re: For all positive integers m, [m]=3m when m is odd and [m]=(1/2)*m when  [#permalink]

Show Tags

New post 22 Apr 2016, 17:28
Intern
Intern
User avatar
Joined: 16 Jul 2015
Posts: 35
GMAT 1: 580 Q37 V33
GMAT 2: 580 Q39 V31
GMAT 3: 560 Q40 V28
GMAT 4: 580 Q37 V32
GMAT 5: 680 Q45 V37
GMAT 6: 690 Q47 V37
Re: For all positive integers m, [m]=3m when m is odd and [m]=(1/2)*m when  [#permalink]

Show Tags

New post 14 Jul 2016, 07:29
I have tried to understand this but not sure if I have got it correct.Pls guide me if I am wrong.So [m]=3m when m is odd ,therefore[9]=3*9 =27 and [6]=1/2*6=3 as m is even ;27*3=81 but answer choices are showing us[] so basically we have to pick an answer choice where the[]=81.Two ways we can get[81] is 3*27 and 1/2*162=[81] .Since we do not have answer option 162,so we go with [27]. But still again in the highlighted parts it is not inside the box[]
Target Test Prep Representative
User avatar
V
Status: Founder & CEO
Affiliations: Target Test Prep
Joined: 14 Oct 2015
Posts: 8622
Location: United States (CA)
Re: For all positive integers m, [m]=3m when m is odd and [m]=(1/2)*m when  [#permalink]

Show Tags

New post 16 Jan 2017, 18:04
1
Guduna wrote:
For all positive integers m, [m]=3m when m is odd and [m]=(1/2)*m when m is even. What is [9]*[6] equivalent to?

A. [81]
B. [54]
C. [37]
D. [27]
E. [18]


We are given that [m] = 3m when m is odd, and [m] = (1/2)*m when m is even, and we must determine the value of [9]*[6].

Since 9 is odd, [9] = 3 x 9 = 27.

Since 6 is even, [6] = (1/2) x 6 = 3.

Thus, [9]*[6] = 27 x 3 = 81.

Now we must determine which “bracketed” answer choice is equal to 81.

Since 27 is odd, we see that [27] = 27 x 3 = 81.

Answer: D
_________________

Scott Woodbury-Stewart

Founder and CEO

Scott@TargetTestPrep.com
TTP - Target Test Prep Logo
122 Reviews

5-star rated online GMAT quant
self study course

See why Target Test Prep is the top rated GMAT quant course on GMAT Club. Read Our Reviews

If you find one of my posts helpful, please take a moment to click on the "Kudos" button.

GMAT Club Bot
Re: For all positive integers m, [m]=3m when m is odd and [m]=(1/2)*m when   [#permalink] 16 Jan 2017, 18:04

Go to page    1   2    Next  [ 24 posts ] 

Display posts from previous: Sort by

For all positive integers m, [m]=3m when m is odd and [m]=(1/2)*m when

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  





Powered by phpBB © phpBB Group | Emoji artwork provided by EmojiOne