Question

Most phone numbers have seven digits after the area code, where each digit can be 0-9. How many different phone numbers can there be in one area code?

A) 4,782,969
B) 282,475,249
C) 10,000,000
D) 823,543

Answer 1

C) 10,000,000

Explanation:

Data provided in the question:

- The phone number is of 7 digits

- we have choices from 0-9

meaning 10 number of choices, 0 1 2 3 4 5 6 7 8 9

we have 10 choices out of 10 for each of the 7 blanks

Therefore,

The total number of different phone numbers can there be in one area code that can be formed

= 10 × 10 × 10 × 10 × 10 × 10 × 10

= 10^7

= 10,000,000