| View previous topic :: View next topic |
| Author |
Message |
ildude02
GMAT Destroyer!
Joined: 13 Jan 2008
Posts: 306
Thanks given: 0
Thanked 6 times in 6 posts
|
 Posted: Fri Jul 04, 2008 1:44 pm Post subject: hard time understadning the question |
 |
|
For a finite sequence of non zero numbers, the number of variations in the sign is defined as the number of pairs of consecutive terms of the sequence for which the product of the two consecutive terms is negative. What is the number of variations in sign for the sequence -1, -3, 2, 5, -4 ,
-6.
1)1
2)2
3)3
4)4
5)5
BTW, can anyone tell me how to copy the questions from a gmat prep screen? I try to right click on the screen when I'm reviewing the question, but I don't get any options to even try to copy the page. I wonder how to copy the question from the prepr screen. Appreciate it. |
|
| Back to top |
|
 |
|
|
parallel_chase
GMAT Destroyer!
Joined: 20 Jun 2007
Posts: 441
Thanks given: 7
Thanked 38 times in 36 posts
Target GMAT Score: 800
|
| Posted: Fri Jul 04, 2008 3:01 pm Post subject: Re: hard time understadning the question |
|
|
| ildude02 wrote: | For a finite sequence of non zero numbers, the number of variations in the sign is defined as the number of pairs of consecutive terms of the sequence for which the product of the two consecutive terms is negative. What is the number of variations in sign for the sequence -1, -3, 2, 5, -4 ,
-6.
1)1
2)2
3)3
4)4
5)5
BTW, can anyone tell me how to copy the questions from a gmat prep screen? I try to right click on the screen when I'm reviewing the question, but I don't get any options to even try to copy the page. I wonder how to copy the question from the prepr screen. Appreciate it. |
I think the the answer is 2, according to me the problem says that in a given sequence variation is defined when two consecutive terms are multiplied and the yield is negative. In the sequence only (-3, 2) and (-4,5) are consecutive and results in negative when multiplied.
Whats the OA?
Coming to your other question:
I dont know about mac but on a PC can you see a print screen button. Hit that button once, open paint brush software in accessories. press CTRL V and save it as JPG. |
|
| Back to top |
|
|
ildude02
GMAT Destroyer!
Joined: 13 Jan 2008
Posts: 306
Thanks given: 0
Thanked 6 times in 6 posts
|
| Posted: Fri Jul 04, 2008 4:02 pm Post subject: |
|
|
What's the logic behind considering -3 and 2 as consecutive terms? The answer is not 2.
I use PC, but I don't see a print screen button on the screen. I wonder how come I don't see the "print" screen. All I see, check answer, correct answer and flag for review. |
|
| Back to top |
|
|
parallel_chase
GMAT Destroyer!
Joined: 20 Jun 2007
Posts: 441
Thanks given: 7
Thanked 38 times in 36 posts
Target GMAT Score: 800
|
| Posted: Fri Jul 04, 2008 4:17 pm Post subject: |
|
|
| ildude02 wrote: | What's the logic behind considering -3 and 2 as consecutive terms? The answer is not 2.
whats the answer is it 1
I use PC, but I don't see a print screen button on the screen. I wonder how come I don't see the "print" screen. All I see, check answer, correct answer and flag for review. |
I am sorry, my bad. On the keyboard. It should say "prt sc" if you are using a notebook. |
|
| Back to top |
|
|
ildude02
GMAT Destroyer!
Joined: 13 Jan 2008
Posts: 306
Thanks given: 0
Thanked 6 times in 6 posts
|
| Posted: Fri Jul 04, 2008 4:53 pm Post subject: |
|
|
thanks for your input about how to copy the screen. It did work, but do I have to exit from the review every time I have to copy it into a word doc? I say that since the review screen never lets me view any other application unless I exit of the review scree. Not sure if there is any way around it?
As for the answer, it's 3. It's a gmat prep question. From the sequence, I was literally looking for concesutive terms before I can pair them, so I started arranging them in a consecutive pattersn but then found zero variations. May be we need to consider the terms as given int he question as consecutive
( though clearly 1, -3, 2, 5 etc are not consecutive). In doing so, I can see three pairs which gives a negative sign.
(1, -3), (-3, 2) and (5, -4). The other pairs(2, 5) and (-4, -6) dont satify the variations definition. Can anyone find better reasoning behing this question? |
|
| Back to top |
|
|
|
|
Stuart Kovinsky
GMAT Instructor
Joined: 08 Jan 2008
Posts: 1015
Thanks given: 0
Thanked 144 times in 133 posts
Location: Toronto
GMAT Score: 800
|
| Posted: Fri Jul 04, 2008 10:43 pm Post subject: Re: hard time understadning the question |
|
|
| ildude02 wrote: | For a finite sequence of non zero numbers, the number of variations in the sign is defined as the number of pairs of consecutive terms of the sequence for which the product of the two consecutive terms is negative. What is the number of variations in sign for the sequence -1, -3, 2, 5, -4 , -6.
1)1
2)2
3)3
4)4
5)5
BTW, can anyone tell me how to copy the questions from a gmat prep screen? I try to right click on the screen when I'm reviewing the question, but I don't get any options to even try to copy the page. I wonder how to copy the question from the prepr screen. Appreciate it. |
If the question is posted correctly, the answer should most definitely be 2.
The question doesn't refer to consecutive numbers, it refers to consecutive terms.
In this sequence, we have the terms:
n1 = -1
n2 = -3
n3 = 2
n4 = 5
n5 = -4
n6 = -6
The only way we get a negative product is if we multiply a positive by a negative. There are 5 possible products of consecutive terms:
n1 * n2 = +3
n2 * n3 = -6
n3 * n4 = +10
n4 * n5 = -20
n5 * n6 = +24
Exactly two of the products are negative.
Looking at your last post, you cited n1 = 1 instead of n1 = -1. If, in fact, the first term is supposed to be +1, then the answer would be 3, since:
n1 * n2 = -3,
giving us a third negative product.
_________________
Stuart Kovinsky, B.A. LL.B.
Academic Co-ordinator
Kaplan Test Prep & Admissions
Toronto Office
1-800-KAP-TEST |
|
| Back to top |
|
|
ildude02
GMAT Destroyer!
Joined: 13 Jan 2008
Posts: 306
Thanks given: 0
Thanked 6 times in 6 posts
|
| Posted: Sat Jul 05, 2008 8:32 am Post subject: |
|
|
| my bad, I just realized I copied -1 instead of 1. Thanks for the posts. |
|
| Back to top |
|
|
|
|
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
You cannot attach files in this forum
You cannot download files in this forum
|
|
"GMAT" and other GMAC™ trademarks are registered trademarks of the Graduate Management Admission Council™. The Graduate Management Admission Council™ does not endorse, nor is it affiliated in any way with the owner or any content on this website. The opinions expressed here are solely those of the author or those of the members of this website. Copyright © 2008 BTG Test Prep, LLC. Powered by phpBB © 2001, 2005 phpBB Group.
|
|
