Question

All 5-digit zip codes in the United States are assigned by region. In Texas, all zip codes begin

with the number 7 while the second digit is restricted to numbers from 5 to 9. There is no
restriction on the remaining digits. How many zip code combinations are possible in Texas?

4,000
5, 000
6, 000
7,000

Answer 1

5,000

Explanation:

`(1)/(7)*(5)/(5-9) (10)/(0-9) *(10)/(0-9) * (10)/(0-9)`