math

a 7 digit phone number has a 3 digit prefix followed by 4 digits.how many different phone numbers are possible??

  1. 👍 0
  2. 👎 0
  3. 👁 84
asked by angela
  1. I assume 0 through 9 are allowed and repeats are possible. For example 000-0000 is allowed.

    How many prefixes?
    10*10*10 = 1,000
    how many digits
    10*10*10*10 = 10,000
    so 10^3 * 10^4 = 10^7 = 10 million
    I guess that is why they needed area codes.

    1. 👍 0
    2. 👎 0
    posted by Damon
  2. 7!=1*2*3*4*5*6*7=... (combinatoric)

    1. 👍 0
    2. 👎 0
    posted by Kassen

Respond to this Question

First Name

Your Response

Similar Questions

  1. Math

    It's a riddle question. All six digits in the number even remember that zero is an even number one digit is use once and all the other digits is used twice is four times the hundreds digit 10 digit is the difference of the ones

    asked by Maria on September 21, 2016
  2. Math

    It's a riddle question. All six digits in the number even remember that zero is an even number one digit is use once and all the other digits is used twice is four times the hundreds digit 10 digit is the difference of the ones

    asked by Maria on September 21, 2016
  3. math

    Neelesh is fond of playing number games. Once when his friends were present he challenged them. He said that he has thought of a five-digit number and anyone who guesses it correctly can use his cycle for a full day. ‘To help

    asked by gayathri on August 13, 2016
  4. A fun one-math

    i am a four -digit number with no two digits the same. my ones digit is twice my thousands digit and one less than my tens digit. my hundreds digit is the difference between my tens digit and my thousands digit. my thousands digit

    asked by manny on August 20, 2007
  5. math

    Two friends are playing a variation of MasterMind where one friend tries to guess the three digit number that the other friend is thinking of. The rules of the game are as follows: -Digits can be repeated -Zero cannot be the first

    asked by S on February 14, 2019
  6. Math

    Solve the mathematical puzzle. Determine the digits of R from these clues. The first digit is the answer when the third digit is divided by 2. The second and third digits add to 7. The second digit minus the first digit is 1. R is

    asked by Shawna Lynn on April 29, 2013
  7. math

    What mystery number has 8 digits; none of the digits are the same. It is evenly divisible by 10. The value of one of the digits is 80,000. The digits in the millions place is the largest 1-digit odd number. The digit in the

    asked by Adonis on April 16, 2012
  8. math

    *The number has 8 digits, none of the digits are the same. *It is evenly divisible by 10. *The value of one of the digits is 80,000 *The digit in the millions place is the largest 1-digit odd number. *The digit in the thousands

    asked by rod on September 25, 2012
  9. Math

    The mystery number's tens digit is less than the ones digit. The tens digit is less than the tenths digit. The tens digit is even. Its ones digit divided by its tens digit is 5. The product of two of the digits is 6 It has two odd

    asked by Gene on September 25, 2012
  10. math

    The number has 8 digits none of the digits are the same 2. It is enemy divisible by 10 3. The value of one of the digits is 80,000 4. The digit in the millions place is the largest 1-digit odd number 5. The digit in the thousands

    asked by zb on January 9, 2013

More Similar Questions