Find the average of all prime numbers between 30 and 50.	Choose one:  A) 30  B) 33.6  C) 39.8  D) 44.9  E) None
Sol.   There are five prime numbers between 30 and 50.   They are 31, 37, 41, 43 and 47   ∴ Required average = [31 + 37 + 41 + 43 + 47 / 5] = 199/ 5= 
<gadget id="calculator">199/ 5</gadget>
<output>199/5 = around 39.8</output>
39.8   Answer 39.8
<result>C</result>
Find the average of all prime numbers between 30 and 50.