This topic has expert replies
Senior | Next Rank: 100 Posts
Posts: 41
Joined: 16 Dec 2008

percentile

by billyr » Thu Feb 26, 2009 9:55 am
How to interpret this question?


Thanks
Attachments
percen.doc
(57.5 KiB) Downloaded 84 times

Senior | Next Rank: 100 Posts
Posts: 76
Joined: 24 Jan 2009
Thanked: 11 times
GMAT Score:730

by BuckeyeT » Thu Feb 26, 2009 10:50 am
Class 1
90th percentile of 80 = 9/10 * 80 = 72 (71 below, 8 above)

Class 2
xth percentile of 100 = x% * 100 = 100 - 19
x * 100 = 81
x = 81/100
= .81 or 81%

Together
Her combined grade rank / Possible ranks
(72 + 81) / (80 + 100)
153 / 180
85% or 85th percentile.

D.

User avatar
GMAT Instructor
Posts: 3650
Joined: 21 Jan 2009
Location: India
Thanked: 267 times
Followed by:80 members
GMAT Score:760

by sanju09 » Wed Apr 08, 2009 6:07 am
Amy was the 90th percentile of the 80 grades for her class, therefore, 10% are higher than Amy's, 10%*80 = 8.

19 of the other class was higher than Amy. Totally, 8 + 19 = 27

Then, the percentile is:

(180 - 27)/180 = 85/100
The mind is everything. What you think you become. -Lord Buddha



Sanjeev K Saxena
Quantitative Instructor
The Princeton Review - Manya Abroad
Lucknow-226001

www.manyagroup.com