Answer:
0.942 is the required probability.
Step-by-step explanation:
We are given the following in the question:
x is a binomial random variable with n = 5 and p = 0.8.
Then,
[tex]P(X=x) = \binom{n}{x}.p^x.(1-p)^{n-x}[/tex]
where n is the total number of observations, x is the number of success, p is the probability of success.
We have to evaluate:
[tex]P(x \geq 3) = P(x = 3) + P(x = 4) +P(x=5)\\\\= \binom{5}{3}(0.8)^3(1-0.8)^2 +\binom{5}{4}(0.8)^4(1-0.8)^1 +\binom{5}{5}(0.8)^5(1-0.8)^0\\\\= 0.2048 +0.4096+0.3276=0.942[/tex]
0.942 is the required probability.