Answer:
28,125
Explanation:
There are 10 digits between 0 and 9. 5 of them are odd, and 5 of them are even.
If a six-digit number has all odd digits, then there are 5 numbers that can be the first digit, 5 numbers that can be the second digit, 5 numbers that can be the third digit, and so on.
The number of permutations is 5×5×5×5×5×5 = 5⁶ = 15,625.
For all even digit numbers, the first digit can't be 0, so the number of permutations is 4×5×5×5×5×5 = 4×5⁵ = 12,500.
So the total permutations of six-digit numbers of equal parity is 15,625 + 12,500 = 28,125.