1. How many of them contain at least one '1'?
2. If I wrote them out in one long line, how many 1 digits would there be?

1st part:

200,000,000?

I tried building a pattern:

If from 1 to 10, there are 2 numbers.                                      If from 1 to 100, there are 20 numbers.

So, as I go on, there will be 20,000,000,000 if taken from 1 to 100??

Right?

Well, for the second part, frankly, lazy to solve. Perhaps to long.