SOLUTION: A new area code is needed for the city. How many options do they have if they cannot use 0 as the first number or the last number in the three digit area code? (remember that they

Algebra ->  Permutations -> SOLUTION: A new area code is needed for the city. How many options do they have if they cannot use 0 as the first number or the last number in the three digit area code? (remember that they      Log On


   

Question 945839: A new area code is needed for the city. How many options do they have if they cannot use 0 as the first number or the last number in the three digit area
code? (remember that they also cannot use 905 or 289 as they are already full)
Answer by Edwin McCravy(20054) About Me  (Show Source):
You can put this solution on YOUR website!
They can choose the first digit any of 9 ways. (can't choose 0)
They can choose the last digit any of 9 ways. (can't choose 0)
They can choose the middle digit any of 10 ways. (can choose 0)
That's 9x9x10 = 810 ways but we must subtract 2 for 905 and 289.

Answer: 810-2 = 808 ways

Edwin