Question

find the sum of the numbers between 100 to 200 which are divisible by 5​

Answer 1

Answer:

2850

Step-by-step explanation:

Numbers between 100 and 200 which are divisible by 5 are:--

105, 110, 115,............190, 195

This forms an A.P with first term a= 105 whose last term, l is 195.

Common difference (d) =5

Now, let the nth term be the last term,

Then, as we know, nth term= a+(n-1) d

=>195= 105+(n-1) ×5

=>195= 105+5n- 5

=>5n= 95

=>n= 19

Now, sum of all the terms of an A.P = {a+l} × n/2

Therefore, required sum, S = (105+195)× 19/2

=> S =300×19/2

=> S =150×19

=> S= 2850.