Question 748723: If you could help me out with this problem i would really appreciate it because i dont understand how to do it!! thank you so much.
Before 1995, area codes had the following format: XYZ
where x=2,3,4...,9; Y=0 or 1; Z=0,1,2,...9.
a)How many area codes were possible before 1995?
b)in 1995 the restrictions were removed from the middle digit, allowing any digit in that position. How many area codes were possible after this change was made?
Thank you so so so very much!!!
Answer by MathTherapy(10555)   (Show Source):
You can put this solution on YOUR website!
If you could help me out with this problem i would really appreciate it because i dont understand how to do it!! thank you so much.
Before 1995, area codes had the following format: XYZ
where x=2,3,4...,9; Y=0 or 1; Z=0,1,2,...9.
a)How many area codes were possible before 1995?
b)in 1995 the restrictions were removed from the middle digit, allowing any digit in that position. How many area codes were possible after this change was made?
Thank you so so so very much!!!
Before 1995, the first digit or X could've been any of 8 digits (2 - 9), or 
The second digit or Y could've been any of 2 digits (0 or 1), or 
The third digit or Z could've been any of 10 digits (0 - 9), or 
Total number of area codes before 1995 =  , or 
After 1995, the first digit or X could've been any of 8 digits (2 - 9), or
The second digit or Y could've been any of 10 digits (0 - 9), or
The third digit or Z could've been any of 10 digits (0 - 9), or
Total number of area codes after 1995 =  , or 
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