Question

complete the following activity​

Answer 1

The least positive three digit natural number divisible by 5 is 100. The sequence divisible by 5 is 100, 105, 110,...,

995.

Now,

an = a + (n − 1)d

→ 995 = 100 + (n − 1) (5) 995 100 + 5n - 5

995 95 + 5n

⇒995 - 95 = 5n

⇒ 5n = 900

⇒ n = 180

Hence, 180 three digit natural numbers are divisible by 5.