Question

what is the sum of all first ten even numbers​

Answer 1

Answer:

GIVEN :-

all first ten even numbers

To FIND :-

the sum of all first ten even numbers

SOLUTION :-

2+4+6+8+10+12+14+16+18+20=110

Answer 2

$\displaystyle\huge\red{\underline{\underline{Solution}}}$

FORMULA TO BE IMPLEMENTED

Sum of first n terms of an arithmetic progression

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

Where First term = a

Common Difference = d

TO DETERMINE

The sum of all first ten even numbers

CALCULATION

The AP IS 2, 4, 6, 8, 10,...... up to 10 terms

First term = a = 2

Second Term = 4

Common Difference = d = 4-2=2

Hence the sum of its first 10 terms is

$= \displaystyle \: \frac{10}{2} [2 \times 2 + (10 - 1) \times 2 ]$

$= 5 \times (4+ 18) = 110$