BREAKING: Target Test Prep releases Brand New 2026 On Demand GMAT prep course

Redeem

GMATPrep Question

This topic has expert replies
Post new topic Post Reply
Previous Topic Next Topic
Junior | Next Rank: 30 Posts
Posts: 12
Joined: Sat Nov 22, 2008 12:07 pm

GMATPrep Question

by steveyb » Tue Dec 30, 2008 1:15 pm
Can someone please explain a quick way to solve this. I don't know OA, since I haven't finished the practice test.

To my understanding, t(1) = 23, so t(2) = 23-3=20, t(3)=17 and so on... until t(10) = 0-3 = -3. However, it is asking for t(n) = -4. I'm sure it's been posted before but I'm not any good at searching for these problems. Thanks


Image
Top
Source: — Problem Solving |
User avatar
Legendary Member
Posts: 2134
Joined: Mon Oct 20, 2008 11:26 pm
Thanked: 237 times
Followed by:25 members
GMAT Score:730

Re: GMATPrep Question

by logitech » Tue Dec 30, 2008 2:00 pm
t2 - t1 = -3
t3 -t2 = - 3
........

tn - t(n-1) = -3

+
------------------

tn-t1 = (n-1) x -3



Since we both know tn and t1

-4-23 = (n-1) x -3

-27 = (n-1) x -3

n-1 = 9

n = 10
LGTCH
---------------------
"DON'T LET ANYONE STEAL YOUR DREAM!"
Top
User avatar
Legendary Member
Posts: 2134
Joined: Mon Oct 20, 2008 11:26 pm
Thanked: 237 times
Followed by:25 members
GMAT Score:730

Re: GMATPrep Question

by logitech » Tue Dec 30, 2008 2:07 pm
In your method: ( which is the BEST method during the test since the numbers are manageable )

1-23 n = 1
2- 20
3- 17
4- 14
5 - 11
6 - 8
7 - 5
8- 2
9 - -1
10 - - 4
LGTCH
---------------------
"DON'T LET ANYONE STEAL YOUR DREAM!"
Top
Post new topic Post Reply
• Page 1 of 1