Question

Find the probability of having 2,3, or 4 successes in five trials of a binomial experiment in which the probability of success is 40%. Round to the nearest tenth of a percent. [ ? ]% ​

Answer 1

65.3%

Explanation:

Binomial distribution PMF below (along with a description)

the probabilty of getting 2, 3, or 4 successes in 5 trials is just

p(2)+p(3)+p(4)

p(2)= 5C2*.4²*(1-.4)³ = .3456

p(3)= 5C3*.4³*(1-.4)²= .2304

p(4)= 5C4*.4⁴*(1-.4)=.0768

.3456+.2304+.0768= .6528