31.how do you solve?
128!
500 of them.
If you mean "between" 100 and 1000 to mean excluding 100 and 1000 then 449. If you want to include 100 and 1000 then 451.
One less than 10000.
There are 2704 of them between 1000 and 10000 inclusive.
There are 2828 integers between 1000 and 9999.
There are 30 such integers.
333 integers.
899
999
Only the multiples of 1000.
31.how do you solve?
Eight of them.
2438 of them.
243
11000