michellecllz michellecllz
  • 13-11-2019
  • Mathematics
contestada

Counting codes. How many 3-digit telephone area codes are
possible if the first digit cannot be 0 or 1?

Respuesta :

Toufiction
Toufiction Toufiction
  • 13-11-2019
There are 10 digits 0 1 2 3 4 5 6 7 8 9 if we can't use 0 and 1 then there are only 8 choices for the first digit and only 2 choices for the second digit and 10 for the third so there are 8*2*10 =160 possibilities.
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