Ask Question
26 January, 06:00

A seven digit phone number consists of a three-digit prefix followed

by four digits. How many different phone numbers are possible for a

particular prefix?

+1
Answers (1)
  1. 26 January, 08:41
    0
    10000 different phone numbers are possible for a particular prefix if repetion of digits is allowed

    5040 different phone numbers are possible for a particular prefix if repetion of digits is not allowed

    Solution:

    Given that,

    A seven digit phone number consists of a three-digit prefix followed by four digits

    We have to find the different phone numbers are possible for a particular prefix

    For a paricualr prefix, there are four digits

    Total numbers from 0 to 9 are 10

    Therefore,

    Different ways for phone number for particular prefix:

    If repetition is allowed:

    Different ways = 10 x 10 x 10 x 10 = 10000 ways

    If repetition is not allowed then:

    Different ways = 10 x 9 x 8 x 7 = 5040 ways
Know the Answer?
Not Sure About the Answer?
Find an answer to your question ✅ “A seven digit phone number consists of a three-digit prefix followed by four digits. How many different phone numbers are possible for a ...” in 📘 Mathematics if you're in doubt about the correctness of the answers or there's no answer, then try to use the smart search and find answers to the similar questions.
Search for Other Answers