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.

Thank you for using the timer!
We noticed you are actually not timing your practice. Click the START button first next time you use the timer.
There are many benefits to timing your practice, including:

What is the average (arithmetic mean) height of the n people [#permalink]
10 Oct 2005, 11:15

00:00

A

B

C

D

E

Difficulty:

5% (low)

Question Stats:

0% (00:00) correct
0% (00:00) wrong based on 0 sessions

What is the average (arithmetic mean) height of the n people in a certain group?

(i) The average height of the n/3 tallest people in the group is 6 feet 2 1/2 inches, and the average height of the rest of the people in the group is 5 feet 10 inches
(ii) The sum of th eheights of the n people is 178 feet 9 inches.

(1)The average height of the n/3 tallest people in the group is 6 feet 2 1/2 inches, and the average height of the rest of the people in the group is 5 feet 10 inches.

(6ft 2.5in)(n/3) = sum of n/3 tallest people's heights
(5ft 10in)(2n/3) = sum of other people's heights

to find the overall average, add the two sums:

([2(5ft 10in)+(6ft 2.5in)]n)/3

when you're calculating the average, you divide by n which takes care of the only variable in the eq'n