22 set 16

Expert replies

radhika1306: Master | Next Rank: 500 Posts; Posts: 144; Joined: Fri Apr 13, 2007 2:25 am

by radhika1306 » Thu Aug 30, 2007 11:54 am

In the sequence of nonzero numbers t1, t2, t3, …, tn, …, tn+1 = tn / 2 for all positive integers
n. What is the value of t5?
(1) t3 = 1/4
(2) t1 - t5 = 15/16

Like this post

Source: Beat The GMAT — Data Sufficiency | Thu Aug 30, 2007 11:54 am

kajcha: Master | Next Rank: 500 Posts; Posts: 321; Joined: Tue Aug 28, 2007 5:42 am; Thanked: 1 times

by kajcha » Thu Aug 30, 2007 12:09 pm

Is the ANS A?

t(n+1) = tn/2

Stmt 1 - t3 = 1/4 => t4 = 1/8 => t5 = 1/16 SUFF

Stmt 2 -> t1-t5 = 15/16 => does not give info for t1 => NOT SUFF

Like this post

ratindasgupta: Senior | Next Rank: 100 Posts; Posts: 98; Joined: Mon Jun 11, 2007 10:32 pm; Location: Mumbai

Re: 22 set 16

by ratindasgupta » Thu Aug 30, 2007 12:15 pm

radhika1306 wrote:In the sequence of nonzero numbers t1, t2, t3, …, tn, …, tn+1 = tn / 2 for all positive integers
n. What is the value of t5?
(1) t3 = 1/4
(2) t1 - t5 = 15/16

1) If t3 = 1/4. we can work out t4 and then t5. So SUFF

2) t1 - t5 = 15/16. Assume t1 as x. So t5 is x/16. So x - x/16 = 15/16. So x = 1. So SUFF

Answer is D

Like this post

kajcha: Master | Next Rank: 500 Posts; Posts: 321; Joined: Tue Aug 28, 2007 5:42 am; Thanked: 1 times

by kajcha » Thu Aug 30, 2007 12:18 pm

Ratin, for second stmt you calculated t5 = 15x/16. Why did you assume x = 1?

Like this post

ratindasgupta: Senior | Next Rank: 100 Posts; Posts: 98; Joined: Mon Jun 11, 2007 10:32 pm; Location: Mumbai

by ratindasgupta » Thu Aug 30, 2007 12:31 pm

kajcha wrote:Ratin, for second stmt you calculated t5 = 15x/16. Why did you assume x = 1?

I have not calculated t5 as 15x/16. if t1 = x, the t2 = x/2, t3 = x/4, t4 = x/8 and t5 = x/16.

So the equation stands as x - x/16 = 15/16. By cross multiplying, you get the valueof x = 1.

Hope this clears it Kajcha.

Like this post

kajcha: Master | Next Rank: 500 Posts; Posts: 321; Joined: Tue Aug 28, 2007 5:42 am; Thanked: 1 times

by kajcha » Thu Aug 30, 2007 12:36 pm

ratindasgupta wrote:
kajcha wrote:Ratin, for second stmt you calculated t5 = 15x/16. Why did you assume x = 1?
I have not calculated t5 as 15x/16. if t1 = x, the t2 = x/2, t3 = x/4, t4 = x/8 and t5 = x/16.

So the equation stands as x - x/16 = 15/16. By cross multiplying, you get the valueof x = 1.

Hope this clears it Kajcha.

Yup, it does.. got confused.. thanks

Like this post

ratindasgupta: Senior | Next Rank: 100 Posts; Posts: 98; Joined: Mon Jun 11, 2007 10:32 pm; Location: Mumbai

by ratindasgupta » Thu Aug 30, 2007 12:41 pm

coolio.

Like this post

Post new topic Post Reply

• Page 1 of 1

GMAT Course Reviews

559 reviews

1168 reviews

431 reviews

359 reviews

147 reviews

5/5

5 Star (560 Reviews)

"Target Test Prep is the closest to the official version of the GMAT exam, about 99% accuracy in terms of the quality and quantity of information. The course has excellently created singular sets of focused lessons and tests for every possible topic that one could come across in the official GMAT exam."

"The TTP course maximizes the efficiency of the time you spend studying. It will take time and effort but I could almost guarantee that if you complete the course exactly as it is laid out you will get an amazing score. They also have a very responsive team willing to help with any questions you might have."

"TTP has two things that I think no other test prep company offers: A teaching approach that reinforces understanding and an attitude that will give you the mental preparedness needed to succeed on the test. TTP gives you a deep understanding of the concept you need to know while teaching you how to think."

Write a Review