Question

find the sum of all natural numbers less than 200 which are divisible by 5

Answer 1

5,10,15,20,25,30,35,40,45,50,55,60,65,70,75,80,85,90,95,100,105,110,115,120,125,130,135,140,145,150,155,160,165,170,175,180,185,190,195 these natural numbers divided by 5.

Answer 2

Answer is "3" first discover the whole of products of 3 that is 3+6+9+...........+198=Sn1=n(a+l)/2

we realize that last term is 198 so "l" is 198 and an is 3 we need to discover n esteem we realize that

Tn =a+(n-1)d 198=3(n-1)3 n=66 Therefore Sn1=66(3+198)/2 =6633.

Therefore the last answer is 19900-9168=10732.