Question

Find the probability of exactly two

successes in five trials of a binomial
experiment in which the probability of
success is 50%.

Round to the nearest tenth of a
percent.

[? ]%

Answer 1

31.3%

Explanation:

Binomial probability distribution

The binomial probability is the probability of exactly x successes on n repeated trials, and X can only have two outcomes.

In which
is the number of different combinations of x objects from a set of n elements, given by the following formula.

And p is the probability of X happening.

Five trials, probability of a success is 50%.

This means that

Probability of exactly two successes

This is P(X = 2). So

0.313*100% = 31.3%