Question

How many area codes were possible before 1995?

Short answer

The number of possible area codes before 1995 is160.

Step-by-step solution

Step 1. Given Information.

Given that before 1995, area codes had the format (XYZ)

where X = 2,3, …, or 9

Y = 0 or 1

Z = 0, 1, 2, …, or 9

It is to be determined how many area codes were possible before 1995.

Step 2. Calculation.

For X there are 8 ways to be selected.

For Y there are 2 ways to be selected.

For Z there are 10 ways to be selected.

By the Fundamental Counting Principle, there are $8\times 2\times 10=160$ different ways to select the 3-digit area code.

Step 3. Conclusion.

Hence, the number of possible area codes before 1995 is 160.