supposed 57% of the population has a retirement account. if a random samples of size 421...

supposed 57% of the population has a retirement account. if a random samples of size 421 is selected, what is the probability that the proportion of persons with a retirement account will differ from the population proportion by less than 4%? Round your answer to four decimal places

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Expert Solution

Solution:

We are given that 57% of the population has a retirement account. Therefore, we have:

It is required to find if a random sample of size 421 is selected, the probability that the proportion of persons with a retirement account will differ from the population proportion by less than 4%.

Therefore, we have to find:

Now using the z-score formula, we have:

Now using the standard normal table, we have:

Therefore, the probability that the proportion of persons with a retirement account will differ from the population proportion by less than 4% is 0.9030

orchestra answered 1 year ago

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