What is the average (arithmetic mean) of eleven consecutive

Question

What is the average (arithmetic mean) of eleven consecutive integers?

1. The average of the first 9 integers is 7. 

2. The average of the last 9 intergers is 9.

Summer3 · Answer

I think the answer should be D.

What is the OA?

BG · Answer

Hi,
Think that D is not correct.
The consecutive integers may be in increasing or decreasing order which will give different results.
Think it is E

Juaz · Answer

Agree D.

integers may be x, x+1, ... x+10 then 
A => 9x+36=63 => x=3 => suff
B => 9x+54=81 => x=3 => suff

nitinneha · Answer

Juaz,

How did you get A => 9x+36=63 and 9x+54=81

s4ur4bh · Answer

A is first nine integars
x, x+1, ... , x+8 = 9x + (1+2+...+8) = 9x + 36 

And in my opinion, we should not worry about calculating the answer. We should concentrate on finding if we can calculate it or not.

Two equations and two variables will give answer. I will leave the question the moment i have the equations.

overtherainbow · Answer

x + (x+1) + (x+2) + ...(x+8) = 9x+ (1+2+3+...+8) = 9x + (8)(9)/2 (sum of consecutive intergers)= 9x+36

hope this clears it up for u

What is the average (arithmetic mean) of eleven consecutive

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