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If numbers can be repeated and zeroes are allowed to lead, this is simply all natural numbers in the set {0000 - 9999}, for a total of 10,000 possible combinations. If numbers cannot be repeated, this becomes a permutation problem; out of 10 possible digits, permute four of them. This evaluates as:
nPr = n! / (n-r)!
10P4 = 10! / (10-4)!
10P4 = 1 * 2 * 3 * ... * 6 * 7 * 8 * 9 * 10 / 1 * 2 * 3 * 4 * 5 * 6
10P4 = 7 * 8 * 9 * 10
10P4 = 5040
There are thus 5,040 possible combinations of four of the digits in 0-9 if any digit is not used twice and 0 is allowed to be a leading digit.
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How many four digit numbers can be formed out of 123 if a digit can be repeated?
There are 3 values (1, 2, 3) for each of the 4 digits. Therefore, there are 3*3*3*3 or 81 four digit numbers that can be formed.
How many four digit whole numbers are there such that the thousand digit is odd the hundreds digit is even and all four digits are different?
5*5*4*4 = 400
What four consecutive 3-digit numbers is 866?
The numbers are 215, 216, 217 and 218.
What four consecutive 3 digit numbers is 866?
The numbers are 215, 216, 217, and 218.
The sum of four 3-digit numbers is 3615?
-3612
How many four digit numbers can be formed using all digits if same digit on four place is not allowed example 5555 is not allowed?
Total possible 4-digit numbers= 1000, 1001,...,9999 = 9000 Total with same digit numbers = 1111,2222,...,9999 = 9 9000 - 9 = 8991
What is the greatest possible sum of two 4 digit numbers?
Add the two greatest possible four digit numbers. 9999 + 9999
How many four digits numbers can be formed using 0123456789?
Assuming that the first digit of the 4 digit number cannot be 0, then there are 9 possible digits for the first of the four. Also assuming that each digit does not need to be unique, then the next three digits of the four can have 10 possible for each. That results in 9x10x10x10 = 9000 possible 4 digit numbers. If, however, you can not use the same number twice in completing the 4 digit number, and the first digit cannot be 0, then the result is 9x9x8x7 = 4536 possible 4 digit numbers. If the 4 digit number can start with 0, then there are 10,000 possible 4 digit numbers. If the 4 digit number can start with 0, and you cannot use any number twice, then the result is 10x9x8x7 = 5040 possilbe 4 digit numbers.
How many four digit numbers are possible from the digit 0'1'2'3'4 numbers may be repeated?
625 if numbers can have leading 0s, 500 otherwise.
What are the odd 4 digit numbers using digits 1470?
1047, 1407, 4017, 4071 are four (out of eight) such numbers.
Using four different digits what is the least sum you can get when you add two digit numbers?
2222
How many 3-digit numbers can be made using the digits 4 6 7 9?
If the digits may be repeated, there are four choices for the first digit, four choices for the second, and four choices for the third. Thus there are 4x4x4 = 64 possible three-digit numbers with those digits. If the digits may not be repeated, there are still four choices for the first digit, but then only three remaining choices for the second, and then just two choices for the third. In this case there are only 4x3x2 = 24 possibilities.
How many four digit numbers can be formed using 3 only once but 3 must be used in all such numbers?
1
How many four-digit odd numbers are possible if the left digit cannot be zero?
9 x 10 x 10 x 5 = 45000
What is the highest and the lowest four-digit numbers?
Lowest four-digit number: 1000 Highest four-digit number: 9999
What is Four Digit numbers?
A four digit whole number can be found from 1000 to 9999
How many four digit numbers can you make using the digit 1 2 3 4 5 6 7 8 9?
3024
