Permutations question

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How many 5 digit odd numbers can be formed from the digits of the number 5 390 462?

I'm not sure how to do this question,
all I know it that the numbers must end in either 5,3, or 9 in order to be odd.

Help please?
Thanks in advance
 
There are some ambiguities about this problem.
So assume that no digit can be used more that once; also assume 04659 does not count as a five digit number. With those assumptions the answer is (5)(5)(4)(3)

We can choose the last digit in three ways, then the first in five ways, etc.
 
sorry, where do you get (5) (5) (4) (3) from..I don't really understand, if you could explain, that would be so much help.
 
Sorry that is a typo.
It should be (5)(5)(4)(3)(3).
We can choose the last digit in three ways, then the first in five ways, etc.
 
Anna, it's really simple; as pka says:

1st digit = 5 ways: 2,4,6 and 2 odds
2nd digit= 5 ways: 0,2,4,6 and 2 odds less the 1st
3rd digit = 4 ways: 0,2,4,6 and 2 odds less the 1st and 2nd
4th digit = 3 ways: 0,2,4,6 and 2 odds less the 1st and 2nd and 3rd
5th digit = 3 ways: 3,5,9

So: 5 * 5 * 4 * 3 * 3 = 900 total numbers

low: 20345
high: 96543
 
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