SOLUTION: How many seven-digit phone numbers are possible if the first two digits cannot be zero or one?

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Question 511581: How many seven-digit phone numbers are possible if the first two digits cannot be zero or one?
Found 2 solutions by oberobic, richard1234:
Answer by oberobic(2304) About Me  (Show Source):
You can put this solution on YOUR website!
7*7*9*9*9*9*9 = 7^2*9^5 = 2,893,401

Answer by richard1234(7193) About Me  (Show Source):
You can put this solution on YOUR website!
There are eight choices for each of the first two digits, and ten choices thereafter.

8*8*10*10*10*10*10 = 6,400,000