ome he proportion of adult women in the United States is approximately 51%. A marketing survey...
The proportion of adult women in a certain geographical region is approximately 51%. A marketing survey telephones 300 people at random. Complete parts a through e below. b) What is the standard deviation of that proportion?
The proportion of adult women in Latvia is approximately 54%. A marketing survey telephones 400 people at random. a) What is the sampling distribution of the observed pro- portion that are women? b) What is the standard deviation of that proportion? c) Would you be surprised to find 56% women in a sample of size 400? Explain. d) Would you be surprised to find 51% women in a sample of size 400? Explain. e) Would you be surprised to find...
11. Gestation Period The length of human pregnancies is approximately normally distributed with mean u = 266 days and standard deviation o = 16 days, (a) What is the probability a randomly selected preg- nancy lasts less than 260 days? (b) What is the probability that a random sample of 20 pregnancies have a mean gestation period of 260 days or less? (c) What is the probability that a random sample of 50 pregnancies have a mean gestation period of...
)A sample survey interviews an SRS of 267 college women. Suppose(as is roughly true) that 70% of all college women have been on a diet within the past 12months. (a) What are the mean and standard deviation of the sampling distribution of the sample proportion ˆpin random samples of size 267? (b) Explain why, under these conditions, the sampling distribution of ˆpis approximately normal. (c) Using the normal approximation, find the probability that 76% or more of the women in...
An article reported that 5% of married couples in the United States are mixed racially or ethnically. Consider the population consisting of all married couples in the United States. (a) A random sample of n = 150 couples will be selected from this population and p̂, the proportion of couples that are mixed racially or ethnically, will be computed. What are the mean and standard deviation of the sampling distribution of p̂? (Round your standard deviation to four decimal places.)...
Assume that the height of adult females in the United States is approximately normally distributed with a mean of 63.8 inches and a standard deviation of 2.83 inches. A sample of 10 such women is selected at random. Find the probability that the mean height of the sample is greater than 62.5 inches. Round your answer to 4 decimal places.
Assume that the height of adult females in the United States is approximately normally distributed with a mean of 63.9 inches and a standard deviation of 2.82 inches. A sample of 10 such women is selected at random. Find the probability that the mean height of the sample is greater than 62.7 inches. Round your answer to 4 decimal places.
Suppose the lengths of the pregnancies of a certain animal are approximately normally distributed with mean mean μ equals 266 and standard deviation sigma equals 27 days What is the probability that a random sample of 18 pregnancies has a mean gestation period of 257 days or less? The probability that the mean of a random sample of 18 pregnancies is less than 257 days is approximately The probability that the mean of a random sample of 18 pregnancies is...
Suppose the lengths of the pregnancies of a certain animal are approximately normally distributed with mean = 125 days and standard deviation 12 days, Complete parts (a) through ( below. Click here to view the standard normal distribution table (page 1). Click here to view the standard normal distribution table (page 2). (b) Suppose a random sample of 20 pregnancies is obtained. Describe the sampling distribution of the sample mean length of pregnancies The sampling distribution of is with s-ando:-D...
3. A sample survey interviews an SRS of 267 college women. Suppose (as is roughly true) that 64 % of all college women have been on a diet within the past 12 months. What are the mean and standard deviation of the sampling distribution for samples of 267 women? The mean of the sampling distribution, p = (+ 0.01) The standard deviation of the sampling distribution of p-hat = (+ 0.01) Use a Normal approximation to find the probability that...