There are 6 light switches on an electrical panel and each can be in the ON and OFF position.

Question

Determine the number of ways that 3 of the switches can be in the ON position  This is a permutation with repeatin items

Answer 1

Arthur is correct.

 

The formula that should be used is total options factorial (6!) divided by each possibility factorial (3!)(3!).

 

6!/(3!)(3!) which equals 6*5*4/(3*2*1) after cancellations. This equals 120/6=20.

 

The answer to your problem is 20 permutations.

 

My apologies Arthur and thank you for pointing out my mistake. I was working on 3 different problems and it was late last night.