The length of human pregnancies is approximately normally distributed with mean 266 days and standard deviation 16 days. Dr. Smith obtains a simple random sample of 10 of her patients and obtains the following results:
279 260 261 266 255 267 230 266 264 240
Construct a 90% confidence interval for the gestation period for all of Dr. Smith's patients. Interpret this interval. .

90% confidence interval for the gestation period for all of Dr. Smith's patients = [250.48 , 267.12] .

Step-by-step explanation:

We are given that the length of human pregnancies is approximately normally distributed with Mean, = 266 days and  standard deviation, = 16 days.

Let suppose, Z = follows N(0,1)

    where, = Sample mean =

                                                     = 258.8

                  n = sample size = 10

So, the 90% confidence interval for is given by ;

 P(-1.6449 < N(0,1) < 1.6449) = 0.90 {because at 10% level of significance z

                                                                table gives critical value of 1.6449}

P(-1.6449 < < 1.6449) = 0.90

P(-1.6449* < < 1.6449* ) = 0.90

P( < < ) = 0.90

So, 90% confidence interval for =  

                                                        =

                                                        = [250.48 , 267.12]

Since, 266 lies inside this interval so we conclude that the mean gestation period for all of Dr. Smith's patients is 266 days.

And this interval states that we have 90% confidence in the above statement.

b.) divide by -5.

step-by-step explanation:

answer: sine

step-by-step explanation: