Sum of the numbers from 1 to 29 is	Choose the correct choice from the following choices:
A) 400
B) 430
C) 435
D) 405
E) none of these

Rationale: explanation : sum of first n natural numbers = 1 + 2 + 3 + . . . . . n = n ( n + 1 ) / 2 substitute n = 29 . so s 20 = 29 ã — 30 / 2 = 435 correct option : c
Answer: C