BREAKING: Target Test Prep releases Brand New 2026 On Demand GMAT prep course

Redeem

11 consecutive integers

This topic has expert replies
Post new topic Post Reply
Previous Topic Next Topic
Master | Next Rank: 500 Posts
Posts: 182
Joined: Sun Aug 02, 2009 7:19 pm
Thanked: 18 times
GMAT Score:680

11 consecutive integers

by sanjana » Wed Oct 14, 2009 2:25 am
if 11 consecutive integers are listed from least to most,what is the mean of the 11 digits?

a)Average of the 1st 9 is 7
b)Average of the last 9 is 9

[spoiler]OA : D[/spoiler]
Top
Source: — Data Sufficiency |
Master | Next Rank: 500 Posts
Posts: 153
Joined: Tue Jun 02, 2009 2:48 pm
Location: Ohio
Thanked: 16 times

Re: 11 consecutive integers

by JeffB » Wed Oct 14, 2009 8:00 am
sanjana wrote:if 11 consecutive integers are listed from least to most,what is the mean of the 11 digits?

a)Average of the 1st 9 is 7
b)Average of the last 9 is 9

[spoiler]OA : D[/spoiler]
For A:
Since we have consecutive integers x + (x+1) etc.

x + (x+1)....(x+8)= 7

You can solve for x (which is your first integer)...Suff

For B:
Same as a

start with (x+2)....(x+10) = 9

Solve for x again..Suff
Top
Post new topic Post Reply
• Page 1 of 1