Consecutive numbers without using a "7"? I tried to calculate the number of consecutive integers between 10,000 and 99,999 that do not use the number 7. I got part of the way there. There are 90,000 numbers(if you start with 10,000) and if you subtract 1/9 of 90,000 that will give you a total of 80,000 that don't begin with a seven. How do you handle the calculation of the the seven in the thousands, hundreds, tens and units place?