Question 992416: How many odd numbers of four digits each can be formed with the digits 0,1,3,5,6 and 7 without repetition ?
Answer by solver91311(24713)   (Show Source):
You can put this solution on YOUR website!
There are 5 ways to select the first digit (only 5 because you cannot use zero as a first digit of a four digit number). Then, because you have to not consider the digit selected for the first digit, but are now allowed to use zero, there are, for each of the 5 ways to select the first digit, 5 ways to select the second digit, for a total of 25 ways to select the first two digits. Then, for each of those 25 ways to select the first two digits there are 4 ways to select the third digit. Then there are 3 ways to select the last digit. 5 X 5 X 4 X 3.
John
My calculator said it, I believe it, that settles it
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