The total number of different phone extensions that can be possible is 90000000 and this can be determined by using the given data.
Given :
A company wants to have 8-digit phone extensions with the first digit not being zero.
The following steps can be used in order to determine the total number of different phone extensions can be possible:
Step 1 - In this problem repetition is allowed.
Step 2 - For the first digit, there are 9 possiblites.
Step 3 - For the second, third, fourth, fifth, sixth, seventh, and eighth digits, there are 10 possibilities.
Step 4 - So, the total number of different phone extensions that can be possible is:
[tex]=9\times 10\times 10\times 10\times 10\times 10\times 10\times 10[/tex]
Step 5 - Simplify the above expression.
= 90000000 different extensions
For more information, refer to the link given below:
https://brainly.com/question/25277954
