Question

(a) Using the binomial distribution; a fair coin is tossed 7 times. What is the
probability of getting?
(i) Exactly 3 tails (ii) at least 5 tails (iii) at the most 3 tails
(iv) Between 3 to 5 tails and (v) 3 heads and 4 tails

Answer 1

Answer:

What is the probability of having 2 heads? (7×6)/2 = 21 outcomes have exactly 2 heads. There are 2^7 = 128 possible outcomes. So the probability = 21/128.