SOLUTION: using the digits 0-9 determine how many 7 digit numbers can be constructed according to the following criteria. The number must be odd and at least 5 million

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Question 881547: using the digits 0-9 determine how many 7 digit numbers can be constructed according to the following criteria. The number must be odd and at least 5 million
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
The numbers must be greater than
or equal to
+5000000+
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The largest 7-digit number is:
+9999999+
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Going from the lowest to the highest,
I have:
EOEO ( starts with odd, and ends with even
So, the evens and odds are the same
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+9999999+-+5000000+=+4999999+
+4999999+%2B+1+=+5000000+ total 7 - digit
numbers possible
+5000000%2F2+=+2500000+
There are 2,500,000 possible odd numbers
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No number starting with 0, 1, 2, 3, or 4 are allowed,
since they would be less than 5,000,000