The new are code has to be 3 _ _

There are ten ways to fill the 2nd digit (0 - 9).

Ignoring the existing area codes, there are 5 ways to fill the last digit (0, 2, 4, 6, 8) *note that 0 is even

By multiplication principle, there are 10 x 5 = 50 codes to choose from.

However, the area code cannot be "306" as it is taken by Saskatchewan.

Hence, the number of possible area codes to choose from = 50 - 1 = 49