Question

In the natural numbers from $10$ to $250$, how are divisible by $4$?

Answer 1

List of natural numbers from 10 to 250 divisible by 4 is:

$12,16,....,248$

$a=12$

$d=4$

$a_n=248$

$a_n=a+(n-1)d$

$248=12+(n-1)4$

$236=(n-1)4$

$59=n-1$

$\therefore n=60$

Therefore there are 60 numbers which are divisible by 4 between 10 and 250.