Question

please answer this question ​

Answer 1

First 100 natural no.s are from 1 to 100

The number of terms divisible by 5 from 1 to 100 are 20

So, the ap is as follows

5, 10, 15,...., 100

a=5

d=5

last term(an) = 100

n=20

So sum of the terms = n/2 [a + an]

                                  =20/2 [5+100]

                                  =10 * 105

                                  =1050

Hope you understood it

Mark me as brianliest plz

Answer 2

Answer:

plz mark me as brilliant and follow me

Step-by-step explanation:

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.