If repetition is allowed [such as 122 or 555], then there are 5³ = 125 possibilities.
There are 10 to the 10th power possibilities of ISBN numbers if d represents a digit from 0 to 9 and repetition of digits are allowed. That means there are 10,000,000,000 ISBN numbers possible.
There are 2 possible digits for the first digit (3 or 4), leaving 3 possible digits for the second digit (5 and 6 and whichever was not chosen for the first), leaving 2 possible digits for the third. Thus there are 2 × 3 × 2 = 12 possible 3 digit numbers.
Interesting.Social Security numbers all have the form: (3 digits) - (2 digits) - (4 digits).That's 9 digits altogether. If you ignore the dashes, you get: xxx,xxx,xxx .With 9 places, there are 1 billion possible different numbers.
The sum is 22 times the sum of the three digits.
89,999 different numbers i guess
Assuming you mean permutations of three digits, then the set of numbers that can be made with these digits is: 345 354 435 453 534 543 There are six possible permutations of three numbers.
There are 10 to the 10th power possibilities of ISBN numbers if d represents a digit from 0 to 9 and repetition of digits are allowed. That means there are 10,000,000,000 ISBN numbers possible.
Interesting.Social Security numbers all have the form: (3 digits) - (2 digits) - (4 digits).That's 9 digits altogether. If you ignore the dashes, you get: xxx,xxx,xxx .With 9 places, there are 1 billion possible different numbers.
There are 2 possible digits for the first digit (3 or 4), leaving 3 possible digits for the second digit (5 and 6 and whichever was not chosen for the first), leaving 2 possible digits for the third. Thus there are 2 × 3 × 2 = 12 possible 3 digit numbers.
There are 9 possible numbers for the first digit (one of {1, 2, ..., 9}); with 9 possible digits for the second digit (one of {0, 1, 2, ..., 9} which is not the first digit)); with 8 possible digits for the third digit (one of {0, 1, 2, ..., 9} less the 2 digits already chosen); This there are 9 × 9 × 8 = 648 such numbers.
The sum is 22 times the sum of the three digits.
89,999 different numbers i guess
With the constraints you have listed, there are only 6 possible phone numbers:202-1178202-1187202-1718202-1781202-1817202-1871The first four digits are fixed, and there are six possible permutations of three different digits.
5040 different 4 digit numbers can be formed with the digits 123456789. This is assuming that no digits are repeated with each combination.
To find the even two-digit numbers where the sum of the digits is 5, we need to consider the possible combinations of digits. The digits that sum up to 5 are (1,4) and (2,3). For the numbers to be even, the units digit must be 4, so the possible numbers are 14 and 34. Therefore, there are 2 even two-digit numbers where the sum of the digits is 5.
It is possible to create infinitely many numbers, of infinitely many different lengths, using the digits of the given number. Using each of the digits, and only once, there are 5! = 120 different permutations.
6 possible 3 digit combonations