Question

what is some of all natural no.laying between 100 and 1000 and multiplles of 5

Answer 1

HEYA MATE, HERE IS UR ANSWER


We can use the concept of AP in these types of question .

a=100

An=1000

d=5 (multiples of 5)

an=a+(n-1)d

1000=100+(n-1)(5)

1000-100= (n-1)5

900=(n-1)5

$\frac {900}{5}$=n-1

180=n-1

180+1=n

n=181

Sn=$\frac {n}{2}$(a+an)

= $\frac{181}{2}$(100+1000)

= $\frac {181}{2}$(1100)

= 181×550

$<b>Sn=99,550$

$\mathbb{Be\:Brainly}$