This is a permutation problem.
The digits are: 0, 1, 2, 3, 4, 5, 6, 7, 8, and 9.
The 1st digit has 9 possibilities (it cannot be zero).
Thus, there are 9(9P9) = 9(9!) = 9(362,880) = 3,265,920 such numbers, because:
The 2nddigit has 9 possibilities (because we are left with 9 digits).
The 3rd digit has 8 possibilities.
The 4th digit has 7 possibilities.
The 5thdigit has 6 possibilities.
The 6thdigit has 5 possibilities.
The 7thdigit has 4 possibilities.
The 8thdigit has 3 possibilities.
The 9thdigit has 2 possibilities.
The 10thdigit has 1 possibility.
so that, 9*9*8*7*6*5*4*3*2*1= 3,265,920.
If repetition of digits isn't allowed, then no13-digit sequencescan be formed from only 5 digits.
I take it that you want to make three digits numbers with 8,7,3, and 6 without repetition. The first digit cane be selected from among 4 digits, the second from 3 digits, the third digit from 2, hence the number of three digit numbers that can be formed without repetition is 4 x 3 x 2 = 24
64 if repetition is allowed.24 if repetition is not allowed.
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.
Six (6)
If repetition of digits isn't allowed, then no13-digit sequencescan be formed from only 5 digits.
24 three digit numbers if repetition of digits is not allowed. 4P3 = 24.If repetition of digits is allowed then we have:For 3 repetitions, 4 three digit numbers.For 2 repetitions, 36 three digit numbers.So we have a total of 64 three digit numbers if repetition of digits is allowed.
I take it that you want to make three digits numbers with 8,7,3, and 6 without repetition. The first digit cane be selected from among 4 digits, the second from 3 digits, the third digit from 2, hence the number of three digit numbers that can be formed without repetition is 4 x 3 x 2 = 24
If the number can contain repeated digits, the answer is 800000. Without repetition, there are 483840.
Assuming that the first digit can't be zero: If repetition of digits is permitted: (5 x 6 x 6) = 180 numbers of 3 digits. If repetition of digits is not permitted: (5 x 5 x 4) = 100 numbers of 3 digits.
64 if repetition is allowed.24 if repetition is not allowed.
There are 7,290 different 4-digit numbers that can be formed from the digits 1-9 without repetition.
-4
If repetition of digits is allowed, then 56 can.If repetition of digits is not allowed, then only 18 can.
-123456787
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.
290