Answer:
a.)The total 4-letters passwords when repetition of letters is allowed are 456976
b.)The total 4-letters passwords when repetition of letters is not allowed are 358800
Step-by-step explanation:
Some situations of <em>probability</em> involve multiple events. When one of the events affects others, they are called dependent events. For example, when objects are chosen from a list or group and are not returned, the first choice reduces the options for future choices.
There are two ways to sort or combine results from dependent events. <em>Permutations</em> are groupings in which the order of objects matters. <em>Combinations</em> are groupings in which content matters but order does not.
How many 4-letter passwords can be made using the letters A throught Z if...
a)Repetition of letters is allowed?
There are only 26 possible values for each letter of the password (The English Alphabet consists of 26 letters). The total 4-letters passwords when repetition of letters is allowed are
b) Repetition of letters is not allowed?
If repetition of letters is not allowed, we can only choose 4 letters out of 26. Using the permutation equation
The total 4-letters passwords when repetition of letters is not allowed are
.