Find the average of first 30 natural numbers.	Pick: A) 20.5 B) 15.5 C) 19.5 D) 19 E) 17
Exp. Sum of first n natural numbers = n( n+1)/2   So, sum of first 30 natural numbers = 30*31/2= 
<gadget id="calculator">30*31/2</gadget>
<output>465</output>
465   Required average=465/30= 
<gadget id="calculator">465/30</gadget>
<output>31/2 = around 15.5</output>
15.5   Answer:15.5
<result>B</result>
Find the average of first 30 natural numbers.