In: Statistics and Probability
Suppose the lengths of the pregnancies of a certain animal are approximately normally distributed with mean
mu equals μ=197 daysand standard deviation sigma equals sσ=14 days. Complete parts (a) through (f) below.
(a) What is the probability that a randomly selected pregnancy lasts less than 192 days?
The probability that a randomly selected pregnancy lasts less than 192 days is approximately 0.3604 (Round to four decimal places as needed.)
Interpret this probability. Select the correct choice below and fill in the answer box within your choice. (Round to the nearest integer as needed.)
B.If 100 pregnant individuals were selected independently from this population, we would expect 36 pregnancies to last less than
192 days.
Suppose a random sample of 20 pregnancies is obtained. Describe the sampling distribution of the sample mean length of pregnancies.
The sampling distribution of x overbarx is normal with mu Subscript x overbar μx equals=197 and sigma Subscript x overbarσxequals=3.1305 (Round to four decimal places asneeded.)
What is the probability that a random sample of 20 pregnancies has a mean gestation period of 192 days or less?
The probability that the mean of a random sample of 20 pregnancies is less than 192 days is approximately 0.0551. (Round to four decimal places asneeded.)
Interpret this probability. Select the correct choice below and fill in the answer box within your choice. (Round to the nearest integer as needed.)
A.If 100 independent random samples of size nequals=20 pregnancies were obtained from this population, we would expect 6 sample(s) to have a sample mean of 192 days or less.
(d) What is the probability that a random sample of 48 pregnancies has a mean gestation period of 192 days or less?
The probability that the mean of a random sample of 48 pregnancies is less than 192 days is approximately 0.0067. (Round to four decimal places asneeded.)
Interpret this probability. Select the correct choice below and fill in the answer box within your choice. (Round to the nearest integer as needed.)
C.If 100 independent random samples of size n equals= 48 pregnancies were obtained from this population, we would expect 1 sample(s) to have a sample mean of 192 days or less.
(e) What might you conclude if a random sample of 48 pregnancies resulted in a mean gestation period of 192 days orless?
This result would be Unusual ▼ so the sample likely came from a population whose mean gestation period is Less than ▼ 197 days.
NOTE: I need to resolve this last question #f and need to know how to do the steps also. Thanks!
(f) What is the probability a random sample of size 19 will have a mean gestation period within 10 days of the mean?
The probability that a random sample of size 19 will have a mean gestation period within 10 days of the mean is _________. (Round to four decimal places as needed.)
I know I have to take =14/sqrt(19) which gives me 3.21182027. I have to divide 10 days by 2 which gives me 5. This is where I get confused .........
(f) What is the probability a random sample of size 19 will have a mean gestation period within 10 days of the mean?
Answer:- Here margin of error (ME) is 10, so you do not need to divide 10 by 2.
Now,
So,
So,
The probability that a random sample of size 19 will have a mean gestation period within 10 days of the mean is 0.9991.
Feel free to ask any query about this through comments! Thank you so much!