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## Main Question or Discussion Point

I am stuck on this. I have three variables (daily, weekly, monthly), they can have a value of yes or no. I need to know the number of possible 'yes' permutations. I use the formula:

n! / (n-r)! which yields '6' i.e., 3*2*1 / (3-3)! --> 6/1 = 6

Yet when I do it by hand:

count Monthly Weekly Daily

1 Yes Yes Yes

2 Yes Yes

3 Yes Yes

4 Yes Yes

5 Yes

6 Yes

7 Yes

By hand I get that there are 7 possible permutations.

My question is the correct formula to use:

(n! / (n-r)! ) + 1 ?

Is there a different formula I should use? What am I assuming incorrectly?

Many thanks!

n! / (n-r)! which yields '6' i.e., 3*2*1 / (3-3)! --> 6/1 = 6

Yet when I do it by hand:

count Monthly Weekly Daily

1 Yes Yes Yes

2 Yes Yes

3 Yes Yes

4 Yes Yes

5 Yes

6 Yes

7 Yes

By hand I get that there are 7 possible permutations.

My question is the correct formula to use:

(n! / (n-r)! ) + 1 ?

Is there a different formula I should use? What am I assuming incorrectly?

Many thanks!