Question

find the sum of first 20 natural numbers
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Answer 1

Step-by-step explanation:

We have to calculate,

$1+2+3+4+….+20$

First term =

$1$

Last term =

$20$

Total number of terms =

$\begin{gathered}\sf{n = 20}\end{gathered}$

Using formula, sum of n terms =

$\begin{gathered}:\implies\sf{ sn = }\dfrac{ n } { 2} {( first Term + Last Term) }\\ \\ \\ :\implies\sf\dfrac{ 20}{2} ( 1 + 20)\\ \\ \\ :\implies\sf{ 210} \end{gathered}$

∴ The sum of first 20 natural numbers is 210.

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