Question

Find sum of all natural numbers between 1 to 300 which are divisible by 5

Answer 1

Step-by-step explanation:

List of all natural number between 1 to 300 which are divisible by 5 are

5,10,15,......300.

a=5

d=10-5=5

tn=300

n=?

Sn=?

tn=a+(n-1)d

300=5+(n-1)5

300=5+5n-5

5n=300

n=300/5

n=60

Sn=n/2 (a+tn) S60=60/2 (5+300)

S60=30 (305)

S60=9150

Therefore,the sum of all natural number 1 to 300 which are divisible by 5 is 9150.