9
By using the 3 digits of a number we can form 3 different two digit numbers. 3C2 = 3!/[(3 - 2)!2!] = 3!/(1!2!) = (3 x 2!)/2! = 3
There are only 999 three digit whole numbers.
On a number line, the digits from 10 to 99 are all two digit numbers. How many numeber are that? There is a short cut. You can subtract 10 from 99 and that gives you the number of numbers between 10 and 99 including 10, but you need to add one more to include 99 as well. So, 10 from 99 is 89 adding 1 is 90 ,which is the amount of numbers total that are two digit. The probability of guessing a two digit number is 1/90 =D
There are many answers. Here is one: 58 and 20
1000there aren't even 1000 three-digitnumbers...There are the digits 1 through 9 for the first digit. Then, we have 0 through 9 for the second digit - excluding the first digit. For the third digit, we have 0 through 9, excluding the two previous digits for a total of 9*9*8 =81*8 =648 three digit numbers with distinct digits.EDIT- ... to be a little more specific, if your talking about a 3-digit password or unlock code its would be 1000. _-_
There are 90 two digit numbers, 10 through 99. There are 18 two digit numbers containing a 9. They are 19, 29, 39, 49, 59, 69, 79, 89, and 90 through 99. Therefore, there are 72 two digit numbers that do not contain a 9.
There are 17 of them.
There are 6804 such numbers.
27: 077,177,277,377,477,577,677,877,977,717,727,737,747,757,767,777,787,797
04,14,24,34,40,41,42,43,44,45,46,47,48,49,54,64,74,84,94.... OR 19 Digits
There is a possible confusion over how the last part of your question ("contain no 5") can be interpreted:it could be a badly written shorthand of the word number: "Nº" also written "No." also written "No" and very badly written as "no", meaning "contains the number 5", meaning "the number 5" - the number between 4 and 6 and less than 10;it could be a badly written shorthand of the word number: "Nº" also written "No." also written "No" and very badly written as "no", meaning "contains the number 5", meaning "the digit 5" - the digit 5 in any place value column;It negates the sense so that "contain no 5" means "do not contain the digit 5".In interpretation number 1 there are no such numbers, as 5 is less than 10 and all two digit numbers are greater than, or equal to 10 (I suspect that this meaning is definitely not intended).There are 90 two digit numbers (10 - 99); of them:9 contain a 5 as the second digit: 15, 25, ..., 9510 contain a 5 as the first digit: 50, 51, ..., 59So there are 19 of the digit 5 used.However, 55 is counted twice, meaning there are 18 numbers which contain the digit 5. (This is the solution to the interpretation number 2.)Which means there are 90 - 18 = 72 numbers which do not contain the digit 5. (The solution to interpretation number 3, which I suspect is the required answer.)Use whichever solution meets your intended interpretation of the question you wrote.
No, and you do not even if you reverse them.
There is only one such number.
Let's count them out... 12 20 21 22 23 24 25 26 27 28 29 32 42 52 62 72 82 92 Whew... that makes 18 two-digit numbers that have a "2".
-99 is the smallest two digit number.-99 is the smallest two digit number.-99 is the smallest two digit number.-99 is the smallest two digit number.
greatest two digit number is 99. smallest whole number is 0 there fore 99-0=99