How many numbers among 1, 2, 3, 1000 are not divisible by 9?
ok so from 1-100 you find the closest number you multiply by to get the closest to 1000. In this case it is 111. so then you know 111 numbers are divisible by 9. 1000-111=889.
889 is the answer
Use complementary counting...
I think I answered this problem few weeks ago...Here: https://web2.0calc.com/questions/help_22327#r1
For this problem, the best way is to use complementary counting. Here's how:
There are 1000 numbers from 1-1000 inclusive. There are 111 multiples of 9 in the 1000 numbers.
Just evaluate 1000-111 to figure out how many numbers in 1-1000 inclusive are not divisible by 9.
There are 889 numbers in 1-1000 inclusive that are not divisible by 9.