OG13 Q91 - Word Problems (Rates/Work) - The Beat The GMAT Forum - Expert GMAT Help & MBA Admissions Advice

OG13 Q91 - Word Problems (Rates/Work)

Expert replies

basso25@: Master | Next Rank: 500 Posts; Posts: 110; Joined: Mon Jan 14, 2013 1:28 pmFollowed by: 2 members; Thanked: 13 times

by basso25@ » Wed Apr 10, 2013 8:14 am

if q is an odd number and the median of q consecutive integers is 120, what is the largest of these integers?

a) q-1/2 + 120
b) q/2 + 119
c) q/2 + 120
d) q+119/2
e) q+120/2

i can't understand the og13 answer explanation insufficient; therefore, please explain how you got the correct answer simply, please.

Like this post

Source: Beat The GMAT — Problem Solving | Wed Apr 10, 2013 8:14 am

GMAT/MBA Expert

Anju@Gurome: GMAT Instructor; Posts: 511; Joined: Wed Aug 11, 2010 9:47 amFollowed by: 86 members; Location: Delhi, India; Thanked: 344 times

by Anju@Gurome » Wed Apr 10, 2013 8:21 am

basso25@ wrote:if q is an odd number and the median of q consecutive integers is 120, what is the largest of these integers?

a) (q-1)/2 + 120
b) q/2 + 119
c) q/2 + 120
d) (q+119)/2
e) (q+120)/2

You haven't posted the options properly.

Easiest method to solve this problem is to plug q = 1.
Hence, there is only one integer : 120.

So the correct option should yield 120 when q = 1.

a) (q-1)/2 + 120 = 120
b) q/2 + 119 = Not integer
c) q/2 + 120 = Not integer
d) (q+119)/2 = 60
e) (q+120)/2 = Not integer

The correct answer is A.

Anju Agarwal
Quant Expert, Gurome

Backup Methods : General guide on plugging, estimation etc.
Wavy Curve Method : Solving complex inequalities in a matter of seconds.

Â§ GMAT with Gurome Â§ Admissions with Gurome Â§ Career Advising with Gurome Â§

Like this post

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 » Wed Apr 10, 2013 8:34 am

basso25@ wrote:if q is an odd number and the median of q consecutive integers is 120, what is the largest of these integers?

a) (q-1)/2 + 120
b) q/2 + 119
c) q/2 + 120
d) (q+119)/2
e) (q+120)/2

Here's another approach.

If q is odd, then the median of the q integers will be the middle number.
So, of the q integers, the middle number is 120
Of the remaining q-1 integers (not counting 120), half of them are greater than 120 and half are less than 120.
In other words, (q-1)/2 of the integers are greater than 120.
Aside: (q-1)/2 represents half of the remaining q-1 integers.
So, to find the biggest number, we'll take the median (120) and add (q-1)/2 to get ...
120 + (q-1)/2
Answer = A

Cheers,
Brent

Brent Hanneson - Creator of GMATPrepNow.com

Like this post

basso25@: Master | Next Rank: 500 Posts; Posts: 110; Joined: Mon Jan 14, 2013 1:28 pmFollowed by: 2 members; Thanked: 13 times

by basso25@ » Wed Apr 10, 2013 8:42 am

anju: sorry about that, thanks for correcting.

anju/brent: thank you both for your explanations; combined, they've given me a stronger hold on this question.

Like this post

vipulgoyal: Master | Next Rank: 500 Posts; Posts: 468; Joined: Mon Jul 25, 2011 10:20 pmFollowed by: 4 members; Thanked: 29 times

by vipulgoyal » Wed Apr 10, 2013 9:17 pm

Brent,
I have a query here
its not necessary that q-1/2 numbers are greater then median
for example 119 119 120 120 120
more over here the geatest is NOT 122
120 + (5-1)/2 = 122
please shed some light

Like this post

GMAT/MBA Expert

Anju@Gurome: GMAT Instructor; Posts: 511; Joined: Wed Aug 11, 2010 9:47 amFollowed by: 86 members; Location: Delhi, India; Thanked: 344 times

by Anju@Gurome » Wed Apr 10, 2013 9:22 pm

vipulgoyal wrote:Brent,
I have a query here
its not necessary that q-1/2 numbers are greater then median
for example 119 119 120 120 120
more over here the geatest is NOT 122
120 + (5-1)/2 = 122
please shed some light

Read the question again.
It said "q consecutive integers"
Your example, '119 119 120 120 120' are not 5 consecutive integers.

Like this post

vipulgoyal: Master | Next Rank: 500 Posts; Posts: 468; Joined: Mon Jul 25, 2011 10:20 pmFollowed by: 4 members; Thanked: 29 times

by vipulgoyal » Wed Apr 10, 2013 9:26 pm

thanks for prompt response, missing my glasses

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