Question

Question:- Find the sum of first 20 natural odd numbers.
Answers:- Given first 20 odd numbers
Square of 20 is 400 is the answer.
Answer is 400.

Answer 1

Answer: 210

Step-by-step explanation:

The first twenty naturai numbers (i.e 1,2,3,4.............,20) forms an AP (arithematic progression) where

a = 1

d = 1

$l=20$

We know that,

$S = \frac{n}{2}(a+l)$

  = $\frac{20}{2}(1+20)$

    = 10(21)

   = 210

HOPE IT HELPS (^_^)