Question

A phone number contains 7 digits. how many different numbers can be made using the digits 0–9 if the first digit is not 0 and all of the digits can be repeated?

Answer 1

9x10^6 is your answer.

Answer 2

So since the first number can’t have zero that means it only has 9 options.
The rest of the 6 numbers have 10 options

9*10^6
= 9,000,000