Find all School-related info fast with the new School-Specific MBA Forum

 It is currently 18 May 2013, 03:32

# The average (arithmetic mean) of the multiples of 6

Author Message
TAGS:
Intern
Joined: 24 Apr 2010
Posts: 27
Followers: 0

Kudos [?]: 3 [0], given: 6

The average (arithmetic mean) of the multiples of 6 [#permalink]  28 May 2010, 13:57
00:00

Question Stats:

63% (02:13) correct 36% (01:52) wrong based on 1 sessions
The average (arithmetic mean) of the multiples of 6 that are greater than 0 and less than 1,000 is

499
500
501
502
503

Could someone explain what the quickest way to solve this is?
Thanks!
GMAT Club team member
Joined: 02 Sep 2009
Posts: 11505
Followers: 1790

Kudos [?]: 9512 [2] , given: 826

Re: The average (arithmetic mean) of the multiples of 6 [#permalink]  28 May 2010, 14:16
2
KUDOS
perseverant wrote:
The average (arithmetic mean) of the multiples of 6 that are greater than 0 and less than 1,000 is

499
500
501
502
503

Could someone explain what the quickest way to solve this is?
Thanks!

Multiples of 6 represent arithmetic progression (aka evenly spaced set). In any evenly spaced set the arithmetic mean (average) is equal to the median and can be calculated by the formula mean=median=\frac{a_1+a_n}{2}, where a_1 is the first term and a_n is the last term.

First term is 6 and last term is 996 (the last even multiple of 3 below 1000). So mean=\frac{6+996}{2}=501.

_________________
Intern
Joined: 24 Apr 2010
Posts: 27
Followers: 0

Kudos [?]: 3 [0], given: 6

Re: The average (arithmetic mean) of the multiples of 6 [#permalink]  28 May 2010, 14:56
Thank you! this is very helpful!

First term is 6 and last term is 996 (the last even multiple of 3 below 1000). So mean=\frac{6+996}{2}=501.
I assume you meant multiple of 6 instead of 3.
GMAT Club team member
Joined: 02 Sep 2009
Posts: 11505
Followers: 1790

Kudos [?]: 9512 [0], given: 826

Re: The average (arithmetic mean) of the multiples of 6 [#permalink]  28 May 2010, 15:12
perseverant wrote:
Thank you! this is very helpful!

First term is 6 and last term is 996 (the last even multiple of 3 below 1000). So mean=\frac{6+996}{2}=501.
I assume you meant multiple of 6 instead of 3.

No. This is how I found the last multiple of 6 below 1000: it would be the last EVEN multiple of 3 (thus multiple of 6) below 1000 .
_________________
Re: The average (arithmetic mean) of the multiples of 6   [#permalink] 28 May 2010, 15:12
Similar topics Replies Last post
Similar
Topics:
If the average (arithmetic mean) of a and b is 45, and the 1 19 Dec 2004, 18:31
1 Is the average (arithmetic mean) of a certain series of 2 18 Apr 2010, 13:45
2 The average (arithmetic mean) of a normal distribution of a 9 16 Aug 2010, 11:25
2 If the average (arithmetic mean) of 6 numbers is 75, how 5 26 Sep 2010, 06:10
The average (arithmetic mean) of a normal distribution 1 15 Jul 2012, 16:36
Display posts from previous: Sort by