Question

What is the sum of first $100$ natural numbers?

Answer 1

Find the sum of first $100$ natural numbers

Natural numbers are those numbers that include all positive integers excluding $0$.

The numbers from $1$ to $100$ are in A.P.

The formula for the sum of the first $n$natural number is $\frac{n\left(n+1\right)}{2}$.

The number of natural numbers for the given series is $100$.

The sum of first $100$ natural numbers is $\frac{100\left(100+1\right)}{2}$

$$\begin{gathered} =50\times 101 \\ =5050 \end{gathered}$$

Hence the sum of first $100$ natural numbers is $5050$.