







Sixdigit telephone numbers 
20200312 

Lulamile pose la question : What is the probability that a sixdigit telephone number has no repeated digits? The telephone number cannot begin with a zero Penny Nom lui répond. 





The last two digits of a phone number 
20160403 

Joshua pose la question : I want to find the last two digits of a phone number whose first eight numbers of a ten digit phone numbers are known. Penny Nom lui répond. 





Missing digits in a phone number 
20150107 

Janelle pose la question : I had a friend try and play a game on me, regarding phone numbers, so I only know the area code , and the last four digits of the phone number. Which means, there are 3 digits that I need to figure out all the possibilities to. Penny Nom lui répond. 





Four digit phone numbers 
20140225 

Tom pose la question : Hi, I'm an online math teacher, working on lessons for my students.
This question is in their book and I can't do it...! Help!
It has to do with phone numbers, and in this problem,
we are only dealing with
the last 4 digits of the number.
It asks how many possible numbers we have
if at least one digit repeats in the last 4 digits of the number. Penny Nom lui répond. 





7 digit phone numbers 
20131208 

Sean pose la question : Hi I was wondering how you would calculate how may 7 digit phone numbers there are with only odd digits? Penny Nom lui répond. 





Missing three digits in a phone number 
20090130 

Elmer pose la question : I have part of a phone number. the first 3 digits are 212, the last digit is four, and the three missing digits are all odd, how many numbers will I have to call to get the right number?
212 _ _ _ 4? Stephen La Rocque and Penny Nom lui répond. 





Some phone numbers 
20080630 

star pose la question : What do you think the probability of finding the last 3 digits of a telephone number if the 1st digit begins with 7? Janice Cotcher and Harley Weston lui répond. 





Phone number combinations 
20070104 

Efrain pose la question : i want to know the different combinations for numbers 7 digits the number are 09 its basically the different phone number combinations example: 5556689 or 5654896 i just want to know for many different combinations are there.... Penny Nom lui répond. 





Phone Number Possibilities 
20000109 

Hamilton Weston pose la question : How do phone companies arrive at the possible number of phone numbers that can be generated for customers? Harley Weston lui répond. 

