According to a recent survey, 31 percent of the residents of a certain state who are age 25 years or older have a bachelor’s degree. A random sample of 50 residents of the state, age 25 years or older, will be selected. Let the random variable B represent the number in the sample who have a bachelor’s degree. What is the probability that B will equal 40 ?

The probability of  getting B=40 is which is negligible.

Step-by-step explanation:

Given that 31 percent of the residents of a certain state who are age 25 years or older have a bachelor’s degree.

Assuming the population of the state aged 25 years or more is Bernoulli's population.

So, when 1 person aged 25 years or more from the state selected randomly, the probability of that person, p, having a bachelor’s degree,

Now, according to Bernoulli's formula, the probability of exactly r success from the total number of sample n is

where p is the probability of success.

Here, a random sample of 50 residents of the state, age 25 years or older, will be selected.

So, n=50.

Given that variable B represents the number in the sample who have a bachelor’s degree,

We have to find the probability that B will equal 40.

So, r=B= 40.

Now, putting these values in equation(ii) and using p=0.25 from equation (i), we have

So, the probability of  getting B=40 is which is negligible.

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step-by-step explanation: