Using the formula for binomial distribution (which I believe to be: nCx ∙ P^x ∙ (1 – P)^(n - x)), how could I determine the probability of rolling less than or equal to 3 fives in 20 rolls of the dice?
I understand the nature of solving a binomial story problem and have come to the following:
Success = Rolling a 5
Probability of success (P) (Is this not what I need to calculate??): p = 1.6
Probability of failure: q = 5/6
Number of trials: n = 20
Number of successes out of those trials: x = 0, x = 1, x = 2, x = 3
I'm really stumped and don't understand where to go from here, any help or advice would be greatly appreciated!