related to permutation and communication
2006-12-17 21:53:45 · 7 answers · asked by twinkle b 1 in Science & Mathematics ➔ Mathematics
total no. of 9 digit no.=9*9*8*7*6*5*4*3*2
=3265920
2006-12-17 22:03:14 · answer #1 · answered by girish sahare 2 · 1⤊ 0⤋
So you're looking for numbers like
1029384756 right?
Total number of combinations of 9 digits is 10! = 3628800
However, 1 in 10 of those will have 0 as the first digit, so multiply by 9/10
3265920
2006-12-18 05:59:41 · answer #2 · answered by Tom :: Athier than Thou 6 · 1⤊ 1⤋
It is 9 * 9 * 8 * 7 * 6 * 5 * 4 * 3 * 2 = 3265920
2006-12-18 06:06:37 · answer #3 · answered by gianlino 7 · 0⤊ 0⤋
a 9 digited no. can be formed using the digits 0,1,2,3,4,5,6,7,8,9
this is same as filling 9 blank places with 10 digits=10P9=10!
But when 0 is in first place,we get an eight digited no.
If the first place is filled with 0,the remaining places can be filled with remaining letters in 9P8=9! ways
hence
No.of eight digited no. formed when 0 is in first place=9P8
=9!
therefore no. of 9 digited no. formed = total no.of digits formed
using all the 10 digits - no. of numbers starting with 0
=10! - 9!=9x9! = 3265920
2006-12-18 06:48:27 · answer #4 · answered by bhargavi 2 · 0⤊ 0⤋
Although there are 999999999 numbers up to 9 digits long, only 999 of these numbers have cube roots that are whole numbers.Its all in the Cube Logic of Whole Numbers.
Now in Comms, communications, that number is Exponential, kinda like the Social Security #s. 111.11.1111, example of a 9 digit number as it is spaciated on the IDs. So if you are dealing with Whole Numbers, no divisions or breaks, there are 999999999. Now square that, and multiply by any # you want, the answer is almost infinite.
2006-12-18 06:32:33 · answer #5 · answered by Yawn Gnome 7 · 0⤊ 1⤋
it is:
9!/9
2006-12-18 06:53:19 · answer #6 · answered by abcd_123 2 · 0⤊ 1⤋
123456789
2006-12-18 07:59:25 · answer #7 · answered by Anonymous · 0⤊ 1⤋