What is the sum of the first 21 natural numbers (starting from 1)?	Choose the most appropriate option
A) 191  B) 201  C) 211  D) 221  E) 231
The sum of n natural numbers = n*(n+1) / 2 = 21*22/2= 
<gadget id="calculator">21*22/2</gadget>
<output>231</output>
231   The answer is 231.
<result>E</result>
What is the sum of the first 21 natural numbers (starting from 1)?