If, J, K, L, M, and N are positive integers in ascending ord

Expert replies

Previous Topic Next Topic

BTGmoderatorDC: Moderator; Posts: 7187; Joined: Thu Sep 07, 2017 4:43 pmFollowed by: 23 members

by BTGmoderatorDC » Fri Jan 25, 2019 4:50 am

Timer

00:00

Answers

Stats

Difficulty—

If, J, K, L, M, and N are positive integers in ascending order, what is the value of L?

(1) The value of K is 3.
(2) The value of M is 7.

OA E

Source: Official Guide

Like this post

Source: Beat The GMAT — Data Sufficiency | Fri Jan 25, 2019 4:50 am

GMAT/MBA Expert

Brent@GMATPrepNow: GMAT Instructor; Posts: 16207; Joined: Mon Dec 08, 2008 6:26 pmFollowed by: 1268 members; Location: Vancouver, BC; Thanked: 5254 times; GMAT Score:770

by Brent@GMATPrepNow » Fri Jan 25, 2019 5:17 am

BTGmoderatorDC wrote:If, J, K, L, M, and N are positive integers in ascending order, what is the value of L?

(1) The value of K is 3.
(2) The value of M is 7.

Given: J, K, L, M, and N are positive integers in ascending order

Target question: What is the value of L?

Statement 1: The value of K is 3.
There are many scenarios that satisfy statement 1. Here are two:
Case a: J = 1, K = 3, L = 4, M = 7, N = 8. In this case, the answer to the target question is L = 4
Case b: J = 1, K = 3, L = 5, M = 7, N = 8. In this case, the answer to the target question is L = 5
Since we cannot answer the target question with certainty, statement 1 is NOT SUFFICIENT

Statement 2: The value of M is 7.
There are many scenarios that satisfy statement 2. Here are two:
Case a: J = 1, K = 3, L = 4, M = 7, N = 8. In this case, the answer to the target question is L = 4
Case b: J = 1, K = 3, L = 5, M = 7, N = 8. In this case, the answer to the target question is L = 5
Since we cannot answer the target question with certainty, statement 2 is NOT SUFFICIENT

Statements 1 and 2 combined
IMPORTANT: Notice that I was able to use the same counter-examples to show that each statement ALONE is not sufficient.
So, the same counter-examples will satisfy the two statements COMBINED.
In other words,
Case a: J = 1, K = 3, L = 4, M = 7, N = 8. In this case, the answer to the target question is L = 4
Case b: J = 1, K = 3, L = 5, M = 7, N = 8. In this case, the answer to the target question is L = 5
Since we cannot answer the target question with certainty, the combined statements are NOT SUFFICIENT

Answer: E

Cheers,
Brent

Brent Hanneson - Creator of GMATPrepNow.com

Like this post

fskilnik@GMATH: GMAT Instructor; Posts: 1449; Joined: Sat Oct 09, 2010 2:16 pmFollowed by: 33 members; Thanked: 59 times

If, J, K, L, M, and N are positive integers in asce

by fskilnik@GMATH » Fri Jan 25, 2019 6:38 am

BTGmoderatorDC wrote:If, J, K, L, M, and N are positive integers in ascending order, what is the value of L?

(1) The value of K is 3.
(2) The value of M is 7.
Source: Official Guide

$$1 \le J < K < L < M < N\,\,\,\,{\rm{ints}}$$
$$?\,\, = \,\,L$$

$$\left( {1 + 2} \right)\,\,\,\left\{ \matrix{
\,K = 3 \hfill \cr
\,M = 7 \hfill \cr} \right.\,\,\,\,\,\,:::\,\,\,\,\,\,\,\left\{ \matrix{
\,{\rm{Take}}\,\,\left( {J,K,L,M,N} \right) = \left( {1,3,4,7,8} \right)\,\,\,\,\,\, \Rightarrow \,\,\,\,\,? = 4 \hfill \cr
\,{\rm{Take}}\,\,\left( {J,K,L,M,N} \right) = \left( {1,3,5,7,8} \right)\,\,\,\,\,\, \Rightarrow \,\,\,\,\,? = 5\, \hfill \cr} \right.\,\,\,\,\,\,\, \Rightarrow \,\,\,\,\,\,\left( {\rm{E}} \right)$$

We follow the notations and rationale taught in the GMATH method.

Regards,
Fabio.

P.S.: if "ascending" is considered the same as "non-descending" (so that J <= K <= L , etc), the correct answer is still (E).

Fabio Skilnik :: GMATH method creator ( Math for the GMAT)
English-speakers :: https://www.gmath.net
Portuguese-speakers :: https://www.gmath.com.br

Like this post

Post new topic Post Reply

• Page 1 of 1

GMAT Course Reviews

560 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