a lock has a code of 5 numbers between 1 and 20 . If no numbers in the code are allowed to repeat, how many different codes could be made?
Thank you
20C5
20 * 19 * 18 * 17 * 16
oobleck is correct
its a code ... so the same numbers can be used in a different order
so ....15,504?
what do i do with these?
20 * 19 * 18 * 17 * 16
To find the number of different codes that can be made, we can use the concept of permutations, as no numbers in the code are allowed to repeat.
The first number in the code can be any number between 1 and 20.
For the second number, since we cannot repeat any numbers, we have 19 options left.
Similarly, for the third number, we have 18 options left, and so on.
Therefore, the total number of different codes that can be made is calculated by multiplying the number of options for each digit together:
Total number of codes = 20 * 19 * 18 * 17 * 16
Simplifying this expression, we get:
Total number of codes = 186,480
So, there are 186,480 different codes that can be made.