Question 1119998
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Smallest 7-digit number:  -9,999,999

Largest 7-digit number:   9,999,999


So from -9,999,999 to -1 inclusive, there are 9,999,999 different numbers, but 999,999 of them have only 6 digits, so there are 9,000,000 negative 7 digit numbers.


Similarly, there are 9,000,000 positive 7 digit numbers.


Consequently, there are 18,000,000 different 7 digit numbers.


If your instructor says you weren't supposed to consider negative numbers, ask "Why?" until the instructor agrees that you should have included them or admits s/he should have asked the question differently.
								
								
John
*[tex \LARGE e^{i\pi}\ +\ 1\ =\ 0]
My calculator said it, I believe it, that settles it
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