Find the average of first 10 natural numbers.  Choose the correct choice
A) 20.5  B) 18  C) 19.5  D) 19  E) 5.5
Exp. Sum of first n natural numbers = n( n+1)/2   So, sum of first 10 natural numbers = 10*11/2= 
<gadget id="calculator">10*11/2</gadget>
<output>55</output>
55   Required average=55/10= 
<gadget id="calculator">55/10</gadget>
<output>11/2 = around 5.5</output>
5.5   Answer:5.5
<result>E</result>
Find the average of first 10 natural numbers.