Question

how many different three letter passwords can be formed from the letters A,B,C,D,E,F, and G if no repetition of letters is allowed? Please someone help I’m stuck on this problem

Answer 1

Answer:

210 passwords

Step-by-step explanation:

We are asked how many different 3 letter passwords can be formed from the letters A, B, C, D, E, F, and G.

If there is no repetition of letters is allowed, then we can choose the arrangement in the form of $^7P_{3}$.

Now, $^7P_{3} = \frac{7!}{(7 - 3)!} = 210$  

So there can be 210 passwords be formed from the above condition. (Answer)