A city has to accommodate for 9.99 million households requiring a telephone number. They are about to issue 8-digit telephone numbers, with 5 as the first digit.
How many different telephone numbers can be created if repetition of digits is allowed?
first digit must be a 5 so the remaining 7 digits can be anything (0-9) but they all start with a 5
107 = 10,000,000 phone numbers
Why did you repeat your question?
The answer on your prior post is correct; this answer is not....