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four digits

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14 items are filed under this topic.
Four digit numbers 2016-09-08
From ning:
0000-9999 there is ten thousand 4-digit numbers. How to find the number of ways that 4 digit are the same? How to prove it by using formula?
Answered by Penny Nom.
A six digit code 2016-05-06
From Ralph:
How many combinations are possible if a "safe" has four buttons and you can use a six digit code? (these are just single press buttons..)For example, this could be one possible combination: Button 4 Button 1 Button 1 Button 3 Button 2 Button 4. Thanks!
Answered by Penny Nom.
Four digit phone numbers 2014-02-25
From Tom:
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.

Answered by Penny Nom.
A 4 digit code 2013-03-26
From chris:
I saw a previous question about a 4 digit code type thing and I was wondering if you could email me that same type of thing. I changed the pin number on my phone's lock screen and I tried hard to remember it, then I had to go help my mom with something and I automatically forgot it and there is no way for me to get back on my phone. I need all of the possible 4 digit number combinations without the numbers 0, 1, or 2. It cannot be repeating, ascending, or descending.
I know you may not want to do all of them, but I really need it.

Answered by Robert Dawson.
Four digit "combinations" using 0124 2013-02-27
From Ayana:
What are all the possible four digit combinations using 0124. Please list them for me. Thank you.
Answered by Penny Nom.
A 4 digit phone lock using the digits 4, 2, 3 and 0 2012-12-24
From Ragu:
I would like to know formula for searching a combination of 4 digit. eg.

I knew my Phone Lock combination is my car plate number 4230. But this time, i used another way around instead of 4230.

But I am sure, there is only this 4 digits only. 4 & 2 & 3 & 0

Answered by Penny Nom.
What numbers can I be? 2010-11-13
From john:
my thousands digit is 2 times my ones digit.my hundreds digit is my ones digit plus 2. my tens digit is the difference between my thousands and hundreds digit what numbers can i be?
Answered by Penny Nom.
Four digit numbers 2010-05-22
From tyeisha:
Whats all the four digit numbers you can come up with using numbers 0-9
Answered by Tyler Wood.
Four-digit combinations 2009-04-18
From Carri:
How many 4-digit combinations can be made out of digits 1, 2, 3, 4, & 5 using each number once? What are the combinations?
Answered by Penny Nom.
Four digit numbers 2009-03-10
From Theresa:
I need to know the number of 4 digit numbers that can be formed using 1-2-3-4 without repeating numbers
Answered by Penny Nom.
Four digit numbers using 1, 0, 2 and 8 2009-01-27
From Mike:
How many combinations of this four digit number 1028 can this produce only using those numbers. Example would be 0000, 0001,0002,0008,0010,0011,0012,0018,etc...
Answered by Penny Nom.
A four digit passcode 2009-01-12
From john:
i have a machine at home that has a four digit passcode and the numbers range from 1 to 4 how can i get all the ways those numbers can be used
Answered by Harley Weston.
Four digit palindromes 2003-05-05
From Heather:
How many palindromes were in between the numbers 1000 and 9999?
Answered by Penny Nom.
4 x abcd = dcba 2002-11-20
From A student:
Say you have a four digit number (e.g. abcd) and you multiply the number by 4. The answer you get will be the reverse order of the number you started with (dcba). What is the number? The four digits (a,b,c,d) cannot be the same number or cannot be repeated.
Answered by Penny Nom and Claude Tardif.



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