Determine the number of 6 digit positive integers combinatorics there is at least one 7

Can find this by finding the number of 6 digit positive integers w/o 7, then subtracting that from the total number of 6 digit postive integersnumber of six digit positive integers  that do not contain 7: there are only 8 digits for the first digit because you cannot have 0 (makes it a non-six-digit number) and cannot have 7. there are 9 digits for the rest of the digits (no 7).total number of six digit positive integers (no zero for the first digit):   number of six digit positive integers  that contain at least 7 is the total number of six digit positive integers  minus the number of six digit positive integers  that do not contain 7.