The mean per capita income is 23,037 dollars per annum with a variance of 149,769. What is the probability that the sample mean would be less than 23013 dollars if a sample of 134 persons is randomly selected? Round your answer to four decimal places.

Probability that the sample mean would be less than 23,013 dollars is 0.2358.

Step-by-step explanation:

We are given that the mean per capita income is 23,037 dollars per annum with a variance of 149,769.

Also, a sample of 134 persons is randomly selected.

Firstly, Let = sample mean

The z-score probability distribution for sample mean is given by;

              Z = ~ N(0,1)

where, = population mean per capita income = 23,037 dollars p.a.

            = standard deviation = = = 387 dollars p.a

           n = sample of persons = 134

So, probability that the sample mean would be less than 23,013 dollars is given by = P( < 23,013 dollars)

      P( < 23,013) = P( < ) = P(Z < -0.72) = 1 - P(Z 0.72)

                                                                    = 1 - 0.7642 = 0.2358

The above probability is calculated using the z-score table.

Therefore, probability that the sample mean would be less than 23013 dollars if a sample of 134 persons is randomly selected is 0.2358.

the first one

step-by-step explanation:

just id the test.