Solution:
The three digit numbers are 100, 101, …, 999
and the numbers divisible by 13, will be 104, 117, 130, …, 988
Here, a = 104, d = 13, l = 988
Tn (l) = a + (n – 1) d
Find the sum of all three-digits natural numbers which are divisible by 13.
Find the sum of all three-digits natural numbers which are divisible by 13.