Aphone 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?

the options are:
a. 10 × 96
b. 9 × 107
c. 9 × 106
d. 107

Step-by-step explanation:

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

In 7 digit phone number, the first number cannot be 0

So only 1  to 9 are used to get the first digit. 9 numbers can be used

other digits can use number from 0 to 9. 10 number can be used

So possible numbers can be made is

well there are two answers for that.

1: you need 120 ones then that will equal up to 120.

2: you could also do one 100 and 2 tens.

those are the answers that i have thought of.