Question

How many natural number are there up to 1000

Answer 1

Answer:

Here the first digit can be from $1 - 9$ and the second digit can be from $0 - 9$ but not the first digit $10 - 1 = 9$. And the third digit can be from $0 - 9$ but not the same as the first and second digit. Therefore total number of natural numbers from $1$ to $1000$ without repetition=$648 + 81 + 9 = 738ways$.

I hope it helps you :)

Answer 2

Answer:

there are 1000 numbers from 1 to 1000