Question

Find the sum of first 123 even natural numbers

Answer 1

Answer:

The sum of first 123 even natural numbers is 15252.

Step-by-step explanation:

To find : The sum of first 123 even natural numbers.

The number series of even natural number is  2, 4, 6, 8, 10, 12, .  .  .  .  .

The first term a = 2

The common difference d = 2

Total number of terms n = 123

Arithmetic progression sum is defined as

$S_n=\frac{n}{2}[2a+(n-1)d]$

Where a is the first term, d is the common difference and n is the number of terms.

Substitute the value in the sum of a.p formula,

$S_{123}=\frac{123}{2}[2(2)+(123-1)(2)]$

$S_{123}=\frac{123}{2}[4+(122)(2)]$

$S_{123}=\frac{123}{2}[4+244]$

$S_{123}=\frac{123}{2}[248]$

$S_{123}=123\times 124$

$S_{123}=15252$

Therefore, The sum of first 123 even natural numbers is 15252.

Answer 2

Step-by-step explanation:

I hope it will help you please mark me as brainlist.......