The sum of first 20 natural numbers is:

Q: The sum of first 20 natural numbers is:

The correct answer is B. The sum of first n natural numbers is given by the formula n(n+1)/2. For n=20, it becomes 20×21/2 = 210. Remember the trick: multiply the number by its next number, then divide by 2.

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Accepted Answer

The sum of first n natural numbers is given by the formula n(n+1)/2. For n=20, it becomes 20×21/2 = 210. Remember the trick: multiply the number by its next number, then divide by 2.