The probability is 5 3 0. That is the probability of each outcome. N P n C x P x 1 P n x.
N number of trials.
K number of successes. Using the formula for p x you obtain the probabilities for x 0 1 2 and 3 red lights. What is the probability that the coin lands on heads more than 3 times. P X nCx px1-pn-x where p is the probability of success In the above equation n C x is used which is nothing but a combination formula.