Check GMAT Club Decision Tracker for the Latest School Decision Releases https://gmatclub.com/AppTrack

 It is currently 26 May 2017, 01:12

### 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

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

# Events & Promotions

###### Events & Promotions in June
Open Detailed Calendar

# If r, s, and t are nonzero integers, is r^5*s^3*t^4 negative

Author Message
TAGS:

### Hide Tags

Manager
Joined: 06 Jul 2011
Posts: 213
Location: Accra, Ghana
Followers: 1

Kudos [?]: 63 [1] , given: 39

If r, s, and t are nonzero integers, is r^5*s^3*t^4 negative [#permalink]

### Show Tags

11 Apr 2012, 15:52
1
KUDOS
4
This post was
BOOKMARKED
00:00

Difficulty:

25% (medium)

Question Stats:

70% (01:58) correct 30% (00:49) wrong based on 187 sessions

### HideShow timer Statistics

If r, s, and t are nonzero integers, is r^5*s^3*t^4 negative?

(1) rt is negative
(2) s is negative

Could someone kindly render a more easily understood explanation than that found in the Quantitative Review 2nd Edition. It would be really appreciated.
[Reveal] Spoiler: OA
Math Expert
Joined: 02 Sep 2009
Posts: 38894
Followers: 7737

Kudos [?]: 106174 [0], given: 11607

Re: If r, s, and t are nonzero integers, is r^5*s^3*t^4 negative [#permalink]

### Show Tags

11 Apr 2012, 16:11
Expert's post
1
This post was
BOOKMARKED
dzodzo85 wrote:
If r, s, and t are nonzero integers, is r^5*s^3*t^4 negative?

(1) rt is negative
(2) s is negative

Could someone kindly render a more easily understood explanation than that found in the Quantitative Review 2nd Edition. It would be really appreciated.

Since r, s, and t are nonzero integers then in order r^5*s^3*t^4 to be negative, only one condition should hold: r and s must have the opposite signs, in this case (r^5*s^3)*t^4=(negative)*(positive)=negative. Notice that if we were not told that given variables are nonzero then there would be one more condition that t must not be zero.

(1) rt is negative --> r and t have the opposite signs. Not sufficient, since no info about s.
(2) s is negative. Clearly insufficient.

(1)+(2) If r is positive then the answer will be YES (since r^5*s^3*t^4=positive*negative*positive=negative) but if r is negative then the answer will be NO (r^5*s^3*t^4=negative*negative*positive=positive). Not sufficient.

Similar questions to practice:
is-x-2-y-5-z-0-1-xz-y-0-2-y-z-98341.html
m21-q30-96613.html
is-x-7-y-2-z-3-0-1-yz-0-2-xz-95626.html

Hope it helps.
_________________
Joined: 29 Mar 2012
Posts: 324
Location: India
GMAT 1: 640 Q50 V26
GMAT 2: 660 Q50 V28
GMAT 3: 730 Q50 V38
Followers: 30

Kudos [?]: 439 [2] , given: 23

Re: If r, s, and t are nonzero integers, is r^5*s^3*t^4 negative [#permalink]

### Show Tags

13 Jun 2012, 11:56
2
KUDOS
Hi,

$$r^5s^3t^4 < 0$$?

Using (1);
rt is -ve,
so, $$r^5s^3t^4 = (rt)^4r^1s^3$$, no clue about s, Insufficient.

Using (2),
s is -ve, r & t are unknown, Insufficient.

Using (1) & (2),
$$(rt)^4r^1s^3$$
$$(rt)^4 > 0$$, and $$s < 0$$
so the expression reduces to$$r^1(-ve)$$, but we still don't know if r is +ve/-ve.

Regards,
Manager
Joined: 13 Feb 2012
Posts: 146
Location: Italy
Concentration: General Management, Entrepreneurship
GMAT 1: 560 Q36 V34
GPA: 3.1
WE: Sales (Transportation)
Followers: 4

Kudos [?]: 7 [0], given: 85

Re: If r, s, and t are nonzero integers, is r^5*s^3*t^4 negative [#permalink]

### Show Tags

05 Sep 2012, 05:25
Once you realize that two exponents are odd and one is even, you know that the you only have to worry about the signs of r and s, thus reducing the complexity.
Picking numbers might also help, I think, even though it might take a bit too long.

_________________

"The Burnout" - My Debrief

Kudos if I helped you

Andy

Director
Status: Verbal Forum Moderator
Joined: 17 Apr 2013
Posts: 612
Location: India
GMAT 1: 710 Q50 V36
GMAT 2: 750 Q51 V41
GMAT 3: 790 Q51 V49
GPA: 3.3
Followers: 78

Kudos [?]: 497 [0], given: 298

If r, s, and tare nonzero integers, is r5s3 t 4 negative? [#permalink]

### Show Tags

28 Sep 2013, 07:52
If r, s, and tare nonzero integers, is $$r^5s^3t^4$$ negative?
(1) rt is negative.
(2) s is negative.
_________________

Like my post Send me a Kudos It is a Good manner.
My Debrief: http://gmatclub.com/forum/how-to-score-750-and-750-i-moved-from-710-to-189016.html

Math Expert
Joined: 02 Sep 2009
Posts: 38894
Followers: 7737

Kudos [?]: 106174 [0], given: 11607

Re: If r, s, and tare nonzero integers, is r5s3 t 4 negative? [#permalink]

### Show Tags

28 Sep 2013, 07:58
honchos wrote:
If r, s, and tare nonzero integers, is $$r^5s^3t^4$$ negative?
(1) rt is negative.
(2) s is negative.

Merging similar topics.
_________________
GMAT Club Legend
Joined: 09 Sep 2013
Posts: 15456
Followers: 649

Kudos [?]: 209 [0], given: 0

Re: If r, s, and t are nonzero integers, is r^5*s^3*t^4 negative [#permalink]

### Show Tags

23 Dec 2015, 01:02
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 Club Legend
Joined: 09 Sep 2013
Posts: 15456
Followers: 649

Kudos [?]: 209 [0], given: 0

Re: If r, s, and t are nonzero integers, is r^5*s^3*t^4 negative [#permalink]

### Show Tags

17 Apr 2017, 03:31
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.
_________________
Re: If r, s, and t are nonzero integers, is r^5*s^3*t^4 negative   [#permalink] 17 Apr 2017, 03:31
Similar topics Replies Last post
Similar
Topics:
3 Is R/S an integer, if R and S are non-zero 2 12 Apr 2016, 21:51
7 If a, b, and c are nonzero integers and z = b^c>, is a^z negative? 5 18 Oct 2016, 07:27
16 If r, s, and t are nonzero integers, is r^5*s^3*t^4 negative 9 11 Apr 2017, 16:52
14 If r and s are negative, is r/s less than 1 ? 8 24 Mar 2016, 07:45
If p, q, and R are non-negative integers such that the 2 22 Aug 2011, 23:03
Display posts from previous: Sort by