Question

find the sum of all natural numbers from 100 to 200 divisible by 4

Answer 1

first term=104 and last term will be 200
Now An=104+(n-1)4
200 =104 +4n - 4
96=4n-4
n=25
S=n/2(a+l)
=25/2(104+200)
=25x152
=3800