SOLUTION: Stoney Creek is running out of phone numbers. They need a new area code for the city. How many options do they have if they cannot use 0 as the first number or the last number in t
Algebra ->
Permutations
-> SOLUTION: Stoney Creek is running out of phone numbers. They need a new area code for the city. How many options do they have if they cannot use 0 as the first number or the last number in t
Log On
Question 945739: Stoney Creek is running out of phone numbers. They need a new area code 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) (Show Source):
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
