An experimental drug has been shown to be 75% effective in eliminating symptoms of allergies in animal studies. A small human study involving six participants is conducted. What is the probability that the drug is effective on half of the participants?

Respuesta :

Answer:

[tex]P(x=3) = 0.1318[/tex]

Step-by-step explanation:

The question illustrates a binomial distribution and the given parameters are:

Given

[tex]n = 6[/tex] -- sample size

[tex]p = 0.75[/tex] --- probability of success

[tex]r = 3[/tex] --- half of the participant

Using the binomial probability formula, we have:

[tex]P_x = ^nC_xp^x(1-p)^{n-x}[/tex]

For x = 3, the probability is:

[tex]P(x=3) = ^6C_3*0.75^3 * (1-0.75)^{6-3}[/tex]

[tex]P(x=3) = 20*0.75^3 * 0.25^3[/tex]

[tex]P(x=3) = 0.1318[/tex]