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4 digits

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18 items are filed under this topic.
4 digit "combinations" 2018-05-18
From Marvin:
I am designing a game, and I need away of figuring this out without having to write numerically all these numbers

4 digit combinations 0 through 13 non-repeating

Answered by Penny Nom.
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.
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.
4-digit positive numbers 2010-02-15
From marjon:
Find the sum of all the 4-digit positive numbers with no zero digit.
Answered by Penny Nom.
A 4-digit phone code 2010-01-21
From pat:
my daughter can`t remember her 4-digit code to unlock her phone. she is pretty sure it starts with a 4. can you help us? my brain is locked up
Answered by Robert Dawson.
Combinations and permutations 2009-05-07
From Renee:
We are trying to figure out the equation or how to solve the problem of how many combinations of 4 digits you can get out of 0-9 without repeating the numbers in a set (i.e., no 0001, 0002) begining with 0123, 0124, 0125 etc Thanks!
Answered by Stephen La Rocque.
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.
4 digit numbers from 1159 2009-03-10
From David:
I have the digits "1159" and need to come up with a complete list of possible four-digit combinations. It does NOT matter the order of the two number ones (1), so this will help eliminate many possibilities.

Separately, it would also help to actually know the actual number of combinations with which I am dealing to start.

David :)

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.
4 digit strings starting with 7 2009-03-03
From Angel:
I need to no all the 4 digit combinations starting with 7 and with no repititions.
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.
A 4 digit passcode 2008-02-16
From Rob:
If there is a 4 digit passcode with only 6 punch in symbols, how many possibilities are there and what are they? symbols are: Y, X, RB, RT, LB, LT. Please get back to me, thanks for your time and help.
Answered by Stephen La Rocque.
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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