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For all positive integers m, [m]=3m when m is odd [#permalink]
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08 Sep 2010, 06:38
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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]
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Last edited by Bunuel on 23 Jul 2013, 10:37, edited 2 times in total.
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Re: Very easy but still got wrong.. Need Your answer [#permalink]
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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: whenxisevenx21whenxisodd2x1then132059.html
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Re: Very easy but still got wrong.. Need Your answer [#permalink]
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08 Sep 2010, 08:01
Bunuel
Thank you so much I didn't look at the answers that they were also in squares..
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Re: Very easy but still got wrong.. Need Your answer [#permalink]
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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.



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For all positive integers m, [m]=3m when m is odd and [m]= [#permalink]
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22 Nov 2011, 18:33
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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]
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Last edited by Bunuel on 07 Apr 2012, 09:28, edited 1 time in total.
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Re: Special Characters [#permalink]
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22 Nov 2011, 22:12
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



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Re: Special Characters [#permalink]
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23 Nov 2011, 06:46
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
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Re: Formula Question  Gmatprep [#permalink]
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10 Jan 2012, 07:59
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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



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Re: For all positive integers m, [m]=3m when m is odd [#permalink]
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03 Apr 2012, 02:41
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Pure deception. Got caught in the trap.



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Re: Very easy but still got wrong.. Need Your answer [#permalink]
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03 Apr 2012, 06:53
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....
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Re: Special Characters [#permalink]
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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.



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Re: Special Characters [#permalink]
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07 Apr 2012, 09:27
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 Question should read: 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.
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Re: For all positive integers m, [m]=3m when m is odd [#permalink]
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21 Jun 2013, 03:47



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Re: PS question help.... [#permalink]
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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. 54c. 36d. 27e. 18The answer would be D because 27= 3*27 = 81  Kudos if the post helped



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Re: Very easy but still got wrong.. Need Your answer [#permalink]
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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: whenxisevenx21whenxisodd2x1then132059.htmlHi 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



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Re: Very easy but still got wrong.. Need Your answer [#permalink]
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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: whenxisevenx21whenxisodd2x1then132059.htmlHi 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.
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Re: For all positive integers m, [m]=3m when m is odd and [m]= [#permalink]
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[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
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Re: For all positive integers m, [m]=3m when m is odd [#permalink]
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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: whenxisevenx21whenxisodd2x1then132059.htmlEasy math but very tricky. Excelent explanation by Bunuel.



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Re: For all positive integers m, [m]=3m when m is odd [#permalink]
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24 Mar 2015, 05:11
Dang, I crosschecked 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



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Re: For all positive integers m, [m]=3m when m is odd and [m]= [#permalink]
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22 Apr 2016, 17:28
Excellent Question...!! Here is my approach Here [9] = 27 [6]=3 => multiplying them we get 81 = 27*3 so [27] SMASH that D
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Re: For all positive integers m, [m]=3m when m is odd and [m]=
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