Find the average of all the numbers between 6 and 30 which are divisible by 4.  Select.
A) 15  B) 18  C) 20  D) 22  E) None
Sol.   Average = (8+12+16+20+24+28 / 6) = 108 / 6= 
<gadget id="calculator">108 / 6</gadget>
<output>18</output>
18   Answer 18
<result>B</result>
Find the average of all the numbers between 6 and 30 which are divisible by 4.