Question 102827: Determine the number of six-digit integers ( no leading zeros) in which the six-digit integer is i) even with no repetitions ii) divisible by 5 no repetitions.
For the 1st one I thought the last number could only be chosen in 5 ways
then that would leave 9 numbers to choose from. 1st number can't be 0 so it can be chosen in 8 ways leaving 8 numbers as the choice for the 3rd number 7 for the 4th 6 for the 5th number. I came up with 67,200 as the answer but the book has 68,880. Where did I go wrong?
Answer by Fombitz(32388)   (Show Source):
You can put this solution on YOUR website! I guess I have some questions.
i) 6 digit integer even with no repetitions, does that mean once I choose an even number, I can no longer choose it. I guess not since the book answer has repeating 8's. Help!
ii)6 digit integer divisible by 5 no repetitions, what does (no repetitions) mean? Divisible by 5 means the last digit is either 0 or 5. SInce 5 is not allowed, then it must be 0.
Please provide some additional explanation to move this forward. Thanks!
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