Answer:
You wrote the numbers from 1 to 9: 9 digits.
You wrote the numbers from 10 to 99: 90*2 = 180 digits.
You have written 189 digits.
Then you wrote another 1994 - 189 = 1805
All the numbers from 100 to 999 have 3 digits
So you wrote 1805/3 = 601 2/3
This means 601 full numbers and 2 digits from the 602. number.
So 100 + 601 - 1 = 700 was the last number you wrote.
Do you agree?
