Question

find the sum of all natural numbers from 1 to 200 which are completely divisible by 3

Answer 1

Answer:

The sum of all natural numbers from 1 to woo divisible by 5 is as under:

Ist term is(a) 5

Last term is(l) 200

common diffrence(d) is 5

number of terms(n) is 40

Using formula :

sum =n÷2 (2(a)+(n-1)d)

=40÷2 (2 (5)+(40-1)5)

=20 (10+195)

=20 (205)

=4100