# Number of combinations

Discrete Mathematics Level pending

In how many ways can you form a 5-digit number such that:

• All digits in the number is only from the set {2, 4, 6, 8}; that is 26842 is acceptable whereas 12468 is unacceptable.
• Every number in {2, 4, 6, 8} must occur at least once; that is 24684 is acceptable whereas 24664 is unacceptable.

If the total number of ways is $$C$$, submit your answer as $$C$$.

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