Student: Find the average of the first 21 natural numbers?\nOptions:\n(A) 8\n(B) 9\n(C) 10\n(D) 11\n(E) 12.
Another student: Let's say, hmmm...

User
Average of the first 'n' natural numbers = (n + 1)/2\nWe get (21+ 1)/2 = 11 Final answer: (D).
Assistant