The average (arithmetic mean) of the even integers from 0 to 80 inclusive is how much greater than the average (arithmetic mean) of the even integers from 0 to 40 inclusive?	Select the correct option:
A) 20
B) 24
C) 28
D) 36
E) 40
The sum of even numbers from 0 to N is 2 + 4 +...+ N   = 2(1 + 2 + ...+ N/2)   = 2(N/2)(N/2+1)/2 = (N/2)(N/2+1)   The average is (N/2)(N/2+1)/(N/2+1) = N/2   The average of the even numbers from 0 to 80 is  80/2= 
<gadget id="calculator"> 80/2</gadget>
<output>40</output>
40   The average of the even numbers from 0 to 40 is  40/2= 
<gadget id="calculator"> 40/2</gadget>
<output>20</output>
20   The answer is 20.
<result>A</result>
The average (arithmetic mean) of the even integers from 0 to 80 inclusive is how much greater than the average (arithmetic mean) of the even integers from 0 to 40 inclusive?