Can some one please help me with this?
How many 10 digit phone numbers have at least one of each odd digit?
$1,3,5,7,9 = 5!*10^5$
I hope this is right. Or did I double count?
Can some one please help me with this?
How many 10 digit phone numbers have at least one of each odd digit?
$1,3,5,7,9 = 5!*10^5$
I hope this is right. Or did I double count?