Find the number of integers in 101000 that can be divided by at least one of 5,7,9
The numbers from 10 to 1000 that can be divided by 5 are (1000-10) / 5 + 1 = 19910 to 1000 that can be divided by 7 are int ((1000-10) / 7) = 14110 to 1000 that can be divided by 9 are int ((1000-10) / 9) + 1 = 11010 to 1000 that can be divided by 5, 7 at the same time are int ((1000-10) / 35) = 2810 to 1000 that can be divided by 5