We have a question from arithmetic progression chapter in we have given first 100 even natural numbers which are divisible by 5 and we have to find their sum.
Book – RS Aggarwal, Class 10, chapter 5C, question no 18
Lost your password? Please enter your email address. You will receive a link and will create a new password via email.
Even natural numbers: 2,4,6,8,10,....
Even natural numbers divisible by 5→10,20,30,40,.... to 100 terms
Here, a=10,d=20−10=10, and n=100
We have,
Sn=n/2(2a+(n−1)d)
=100/2[2×10+(100−1)10]
=50500.