In a sequence of terms in which each term is three times the : DS Archive
Check GMAT Club Decision Tracker for the Latest School Decision Releases http://gmatclub.com/AppTrack

 It is currently 16 Jan 2017, 15:01

### 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

# In a sequence of terms in which each term is three times the

Author Message
SVP
Joined: 16 Jul 2009
Posts: 1628
Schools: CBS
WE 1: 4 years (Consulting)
Followers: 42

Kudos [?]: 1053 [0], given: 2

In a sequence of terms in which each term is three times the [#permalink]

### Show Tags

30 Jul 2009, 13:00
00:00

Difficulty:

(N/A)

Question Stats:

100% (01:13) correct 0% (00:00) wrong based on 27 sessions

### HideShow timer Statistics

This topic is locked. If you want to discuss this question please re-post it in the respective forum.

In a sequence of terms in which each term is three times the previous term, what is the fourth term?

(1) The first term is 3.

(2) The second-to-last term is 310.
_________________

The sky is the limit
800 is the limit

GMAT Club Premium Membership - big benefits and savings

Manager
Joined: 16 Apr 2009
Posts: 243
Schools: Ross
Followers: 3

Kudos [?]: 83 [0], given: 10

### Show Tags

30 Jul 2009, 13:12
Quote:
In a sequence of terms in which each term is three times the previous term, what is the fourth term?

(1) The first term is 3.

(2) The second-to-last term is 310.

IMO OA is A

Stat 1

first term is 3
the second term would be 3(3)
the third term-3(9)
the fourth term -3(27) =81

Stat 2
we don't know the last term
hence insuff.
_________________

Keep trying no matter how hard it seems, it will get easier.

Manager
Joined: 07 Apr 2009
Posts: 145
Followers: 1

Kudos [?]: 12 [0], given: 3

### Show Tags

31 Jul 2009, 06:25
Quote:
Stat 2
we don't know the last term
hence insuff.

hey infact we do know the last term,but we dont know the number of terms in the sequence and the first term in the sequence and hence cant find out the 4th term, correct ?
Intern
Status: Applying
Joined: 30 Jul 2009
Posts: 38
Followers: 0

Kudos [?]: 4 [0], given: 3

### Show Tags

31 Jul 2009, 11:00
[EDIT - REMOVED BY USER]

Last edited by nplaneta on 17 Jun 2012, 06:01, edited 1 time in total.
Manager
Joined: 22 Mar 2008
Posts: 56
Followers: 1

Kudos [?]: 15 [0], given: 1

### Show Tags

02 Aug 2009, 21:49
skpMatcha wrote:
Quote:
Stat 2
we don't know the last term
hence insuff.

hey infact we do know the last term,but we dont know the number of terms in the sequence and the first term in the sequence and hence cant find out the 4th term, correct ?

1) is sufficient for sure.
but 2 also give some info about last term, no. of terms and first term.
here it goes,
Since each term is three times the previous term, the series is a GP with common ratio 3.
let's say there are N+1 terms in the series and first term is a.
so, the second to last term is the nth term, which can be expressed as, a*(3^(n-1) ).
by statement 2, second-to-last-term is 310.
so, a*(3^(n-1) ) = 310 = 2*5*31.
since 310 does not have 3 as a factor, so a= 310 and 3^(n-1) must be 1
or , n-1 = 0
therefore n = 1
and n+1 = 2.
so, we get first term = 310 and total no of terms =2. and common ratio 3.
so we can get the other terms of the series.

BUT, here i have a doubt. if the total number of terms = 2, 4th term does not come into picture.
curious to know the OA.
Re: sequence of terms   [#permalink] 02 Aug 2009, 21:49
Display posts from previous: Sort by