14. All phone numbers consist of a three-digit area code, a three-digit exchange, and then a four-digit number. A town uses the

Question

3 years ago

12

14. All phone numbers consist of a three-digit area code, a three-digit exchange, and then a four-digit number. A town uses the

587 area code and the exchange 355; for example, 587-355-1234. How many different phone numbers are possible in this town under the following
conditions?

a) At least one digit repeats in the last four digits of the phone number.

Mathematics

1 answer:

Oliga [24] · Answer 1 · 2022-02-16T20:57:51+03:00

Oliga [24]3 years ago

3 0

ANSWER

9000

= 1 X 1 X 9 X 10 3 = 9000