Question

the sum of all natural numbers from 100 to 300 which are exactly divisible by 4 or 5 is​

Answer 1

In order to find the sum, we shall first identify the series,

100,104,108,……..300 it is in Arithmetic progression

first term,a=100

Common difference,d=4

Last term=300

Now, we know the nth term in the A. P can be written as a+(n-1)d=300

n-1=(300–100)/4=50