24
17
3 digit numbers are lessthan 4 digit numbers
-2
There are 90 such numbers.
24
17
3 digit numbers are lessthan 4 digit numbers
There are 2941 4-digit numbers such no two of its digits differ by 1.
There are 16 4-digit numbers that can be made up from 9 and 6.
-2
12 numbers
There are 90 such numbers.
There are 9000 4-digit numbers in hindu-arabic numeration system
9999
4
90