Find all School-related info fast with the new School-Specific MBA Forum

 It is currently 27 Apr 2015, 12:47

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

PS- GMAT Prep

Author Message
TAGS:
Intern
Joined: 21 Apr 2006
Posts: 18
Location: San Francisco, CA
Followers: 0

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

PS- GMAT Prep [#permalink]  21 Jun 2006, 21:34
00:00

Difficulty:

(N/A)

Question Stats:

0% (00:00) correct 0% (00:00) wrong based on 0 sessions
Ok, I am stumped. How does one solve this question? Any clear & concise explanation will be appreciated.

2 Days till GMAT,
Tru
Attachments

math_01.gif [ 14.24 KiB | Viewed 532 times ]

 Kaplan Promo Code Knewton GMAT Discount Codes GMAT Pill GMAT Discount Codes
VP
Joined: 25 Nov 2004
Posts: 1495
Followers: 6

Kudos [?]: 38 [0], given: 0

Re: PS- GMAT Prep [#permalink]  22 Jun 2006, 00:00
t1 = 23
t2 = t1-3 = 23-3 = 20
t3 = t2 - 3 = t1 - 3 - 3 = t1 - 2 (3) = 23 - 2 (3) = 17
t4 = t3 - 3 = t2 - 3 - 3 - 3 = t1 - 3 (3) = 23 - 3 (3) = 14

we can establish a relationship as under:

tn = t1 - (n-1) (3)
-4 = t1- (n - 1) (3)
(n -1) (3) = 23 +4
(n-1) (3) = 27
n = 9 +1 = 10
VP
Joined: 15 Jun 2006
Posts: 1124
Schools: Chicago Booth
Followers: 4

Kudos [?]: 40 [0], given: 0

Every term of sequence is previous term minus three, sequence is
23-20-17-14-11-8-5-2-(-1)-(-4)
(-4) is the 10th term
Manager
Joined: 01 Jun 2006
Posts: 141
Followers: 1

Kudos [?]: 2 [0], given: 0

We have t(n)=t(1)-(n-1)*3
So if t(n)=-4 => 23-3*(n-1)=4 => n=10
VP
Joined: 02 Jun 2006
Posts: 1267
Followers: 2

Kudos [?]: 42 [0], given: 0

You can quickly go from t1 = 23 and list out the values
{23, 20, 17, 14, 11, 8,5,2,-1, -4} i.e. 10
Intern
Joined: 21 Apr 2006
Posts: 18
Location: San Francisco, CA
Followers: 0

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

It's all about the pattern! Thank you everyone.

-Tru
Director
Joined: 06 May 2006
Posts: 781
Followers: 3

Kudos [?]: 16 [0], given: 0

tn = t1 + (n-1)d; question specifies d = -3

=> -4 = 23 - 3n + 3 => n = 30.
Director
Joined: 07 Jun 2006
Posts: 513
Followers: 10

Kudos [?]: 90 [0], given: 0

brcinsf wrote:
It's all about the pattern! Thank you everyone.

-Tru

Use nth term of a sequence = first_term+(n -1)(difference_in_terms)
(or usually remembered as Tn = a+(n-1)d

so -4 = 23 + (n-1)(-3) = 23 -3n +3

-4 = 26 -3n => n =10
_________________

http://onwardtomba.blogspot.com - MBA, GMAT, INSEAD - the journey.
My 7 GMAT Quant Strategies/Trap
My GMAT Debrief

Similar topics Replies Last post
Similar
Topics:
PS- GMAT Prep 8 21 Jun 2006, 21:36
GMAT Prep PS - Geometry 5 11 Jun 2006, 18:09
PS- x (GMAT Prep) 4 31 May 2006, 01:37
PS-GMAT prep 9 23 Feb 2006, 15:25
PS-GMAT prep 3 23 Feb 2006, 15:12
Display posts from previous: Sort by