SOLUTION: How many seven-digit telephone number can be formed if the first three digits cannot be 800 and the first digit cannot be 0?
Algebra.Com
Question 779176: How many seven-digit telephone number can be formed if the first three digits cannot be 800 and the first digit cannot be 0?
Answer by stanbon(75887) (Show Source): You can put this solution on YOUR website!
How many seven-digit telephone number can be formed if the first three digits cannot be 800 and the first digit cannot be 0?
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1st digit:: 8 ways
2nd digit:: 9 ways
3rd digit:: 9 ways
4th thru 7th:: 10
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Total:: 8*9^2*10^4 = 6480000 numbers
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Cheers,
Stan H
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