Question

What is une sum of all natural numbers between 1 and 150 (both included) which are multiples of 3​

Answer 1

Answer:

Here's your answer;

We know that, Nth term of an AP = a + (n - 1)d  

⇒ 3 + (n - 1)3 = 150 ⇒ n = 50

Sum of n terms of an AP = n/2 (2a + (n - 1)d)

a = 3, n = 50 and d = 3

Sum = 50/2 × (6 + 49 × 3) = 3825

So, your answer is 3825.

Hope, this helps you.