GMAT Question of the Day - Daily to your Mailbox; hard ones only

It is currently 13 Nov 2019, 07:16

Close

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
Your Progress

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

Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.

Close

Request Expert Reply

Confirm Cancel

In a certain sequence, the term

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
TAGS:

Hide Tags

Find Similar Topics 
GMAT Club Legend
GMAT Club Legend
User avatar
V
Joined: 12 Sep 2015
Posts: 4055
Location: Canada
In a certain sequence, the term  [#permalink]

Show Tags

New post 26 Oct 2016, 12:52
1
Top Contributor
00:00
A
B
C
D
E

Difficulty:

  25% (medium)

Question Stats:

77% (01:36) correct 23% (01:22) wrong based on 104 sessions

HideShow timer Statistics

In a certain sequence, every term, tn, is given by the formula tn = (k)(n) + 15, for some constant k and for all n > 1. What is the value of t10?

(1) t8 - t7 = 5
(2) (t8)/(t7) = 11/10

*Kudos for all correct solutions

Here's our video solution: https://www.gmatprepnow.com/module/gmat ... /video/940

_________________
Test confidently with gmatprepnow.com
Image
Manager
Manager
avatar
Joined: 05 Jun 2015
Posts: 75
Location: United States
WE: Engineering (Transportation)
Re: In a certain sequence, the term  [#permalink]

Show Tags

New post 26 Oct 2016, 18:13
3
To find the 10th term, we need to know the value of k. It is sufficient to check whether we can find the value of k from the two options

(1) \(t8 - t7 = 5\)
\(8K+15 -(7K+15)= 15\)
k = 5

(1) is Sufficient

(2) (t8)/(t7) = 11/10
\(\frac{8k+15}{7k+15} = \frac{11}{10}\)
this is a linear equation in k, k can be found out.

(2) is also sufficient.

Hence Option D
Manager
Manager
avatar
Joined: 29 Aug 2008
Posts: 103
Re: In a certain sequence, the term  [#permalink]

Show Tags

New post 26 Oct 2016, 22:55
2
tn = K(n) + 15

t10 = ?

Statement 1 = 8k + 15 - 7k - 15 = 5, we can solve for x and find t10. Sufficient.

Statement 2 = (8k + 15)/(7k + 15) = 11/10, single variable equation, we can solve for K and find t10, Sufficient.

Option D.
Intern
Intern
avatar
Joined: 20 Aug 2014
Posts: 3
Re: In a certain sequence, the term  [#permalink]

Show Tags

New post 31 Oct 2016, 05:10
1
t10=10k+15

So, value of k required. k=??

(1) t8−t7=5

8K+15−(7K+15)=5
k = 5

(1) is Suff

A or D

(2) (t8)/(t7) = 11/10
8k+15/7k+15=11/10

From here, k can be found.

(2) is also Suff

Option D
Intern
Intern
avatar
B
Status: GMAT_BOOOOOOM.............. Failure is not an Option
Joined: 22 Jul 2013
Posts: 11
Location: India
Concentration: Strategy, General Management
GMAT 1: 510 Q38 V22
GPA: 3.5
WE: Information Technology (Consulting)
GMAT ToolKit User
Re: In a certain sequence, the term  [#permalink]

Show Tags

New post 24 Nov 2016, 03:40
Based on the given formula :tn = (k)(n) + 15

Find out t10 It means t10 = 10K + 5 . So if we are able to find K then t10 can be found.

Statement 1 : t8−t7=5
==> 8k +15 - 7k -15 = 5
K = 5 Hence Sufficient

Statement 2 : (t8)/(t7) = 11/10

(8k+15)/ (7k+15) = 11/10

Cross multiply and get the value of the K .Hence Sufficient .

Answer D




Kudos will be appreciated if it was helpful. :)
_________________
Kudos will be appreciated if it was helpful. :)

Cheers!!!!
Sit Tight and Enjoy !!!!!!! :)
Non-Human User
User avatar
Joined: 09 Sep 2013
Posts: 13570
Re: In a certain sequence, the term  [#permalink]

Show Tags

New post 20 Oct 2018, 07:28
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 Bot
Re: In a certain sequence, the term   [#permalink] 20 Oct 2018, 07:28
Display posts from previous: Sort by

In a certain sequence, the term

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  





Powered by phpBB © phpBB Group | Emoji artwork provided by EmojiOne