SOLUTION: How many odd 4-digit numbers are there (repetition is allowed)?

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Question 1010367: How many odd 4-digit numbers are there (repetition is allowed)?
Found 2 solutions by stanbon, Alan3354:
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
How many odd 4-digit numbers are there (repetition is allowed)?
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thousands digit:: 9 ways
hundreds digit::: 10 ways
tens digit:: 10 ways
units digit must be even:: 5 ways
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Ans: 9*100*5 = 9*500 = 4500
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Cheers,
Stan H.
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Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
How many odd 4-digit numbers are there (repetition is allowed)?
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If leading zeroes are allowed, eg 0001, there are 10000 total numbers.
If not, it's 1000 to 9999 = 9000 and half of them are odd.
--> 4500