+36916 from 1000 to 9999 is 9000 numbers
stating with 1001 and ending with 9996 there are 9000/7 =~ 1286 numbers ARE divisible by 7....
you can finish.....
+169 YEE complementary counting!
yes
so basically, what that is guest is you count the solutions you DONT want, then subtract. This is because it is sometimes faster this way.
