The weights of running shoes are normally distributed with an unknown population mean and standard deviation. If a random sample of 23 running shoes is taken and results in a sample mean of 12 ounces and sample standard deviation of 3 ounces, find the margin of error, ME, for a 95% confidence interval estimate for the population mean using the Student's t-distribution.

The margin of error for a 95% confidence interval estimate for the population mean using the Student's t-distribution is of 6.22 ounces.

Step-by-step explanation:

The first step to solve this problem is finding how many degrees of freedom, we have. This is the sample size subtracted by 1. So

df = 23 - 1 = 22

95% confidence interval

Now, we have to find a value of T, which is found looking at the t table, with 22 degrees of freedom(y-axis) and a confidence level of . So we have T = 2.0739

The margin of error is:

M = T*s

In which s is the standard deviation of the sample.

In this question:

s = 3.

Then

M = 2.0739*3 = 6.22

The margin of error for a 95% confidence interval estimate for the population mean using the Student's t-distribution is of 6.22 ounces.

step-by-step explanation:

i found the life tables for the year 2012. 

life table of males at age 30. probability of dying between ages x and x+1

total population:  

29–30 . . . . . . . . . . . . 0.001030

30–31 . . . . . . . . . . . . 0.001061

males:  

29–30 . . . . . . . . . . . . 0.001420

30–31 . . . . . . . . . . . . 0.001448

white population

29–30 . . . . . . . . . . . . 0.001005

30–31 . . . . . . . . . . . . 0.001037

white males

29–30 . . . . . . . . . . . . 0.001372

30–31 . . . . . . . . . . . . 0.001399

non hispanic white population

29–30 . . . . . . . . . . . . 0.001083

30–31 . . . . . . . . . . . . 0.001116

non hispanic white males

29–30 . . . . . . . . . . . . 0.001477

30–31 . . . . . . . . . . . . 0.001503

jacob, non hispanic white male. 30 years old.

probability that jacob lives to be 30 years old. 

since the given probabilities are probabilities of dying, i think we simply subtract it from 1 to get the probability of living. we will use the probability of non hispanic white male.

                                          probability of living to be 30 y.o.

29 - 30 : 1 - 0.001477 = 0.998523

30 - 31 : 1 - 0.001503 = 0.998497