Question

How many 9-digit numbers (that is numbers between 100,000,000 and 999,999,999)

a) Are even? (type a whole number)

b) Are divisible by 5? (type a whole number)

c.) Are divisible by 25? ( type a whole number)

Answer 1

a) Even number is something which is divisible by 2.

So, number of even numbers =

So, there are total 450000000 even numbers.

b) Divisible by 5 =

c) Divisible by 25 =

The reason to add 1 in all because when we subtract 100000000 there then we are removing that 100000000 also whereas that's part of 9 digits number. That's why we need to add 1 there.

I hope this will help. Thank you.