Data management
posted by Lisa .
from the digits 0,1,2,3,4,5,6,7,8,9 find the number of
a) 4digit numbers with repetition of digits
b) 4digit numbers without repetition of digits
c) the number of odd 4digit numbers with no repetition of digits
d) the number of even 4digit numbers with no repetition of digits

We will be glad to criti9ue your thinking.
For (a), how many numbers are between 0 and 9999? Some have repeated digits.
These are not hard when you think about them