Question

1.You measure 26 textbooks' weights, and find they have a mean weight of 69 ounces. Assume the population standard deviation is 9.7 ounces. Based on this, construct a 95% confidence interval for the true population mean textbook weight.

Give your answers as decimals, to two places

_____ < μμ < _____

2.In a sample of 180 adults, 155 had children. Construct a 90% confidence interval for the true population proportion of adults with children.

Give your answers as decimals, to three places

_____< p < _____

3.Business Weekly conducted a survey of graduates from 30 top MBA programs. On the basis of the survey, assume the mean annual salary for graduates 10 years after graduation is 126000 dollars. Assume the standard deviation is 30000 dollars. Suppose you take a simple random sample of 54 graduates.

Find the probability that a single randomly selected salary is more than 120000 dollars.
P(X > 120000) =

Find the probability that a sample of size n=54n=54 is randomly selected with a mean that is more than 120000 dollars.
P(M > 120000) =

4.You measure 21 watermelons' weights, and find they have a mean weight of 41 ounces. Assume the population standard deviation is 3.2 ounces. Based on this, construct a 90% confidence interval for the true population mean watermelon weight.

Give your answers as decimals, to two places

_________ ±±_____ ounces

5. Business Weekly conducted a survey of graduates from 30 top MBA programs. On the basis of the survey, assume the mean annual salary for graduates 10 years after graduation is 135000 dollars. Assume the standard deviation is 38000 dollars. Suppose you take a simple random sample of 66 graduates.

Find the probability that a single randomly selected salary is at most 139000 dollars.
Answer =

Find the probability that a sample of size n=66n=66 is randomly selected with a mean that is at most 139000 dollars.
Answer =

Enter your answers as numbers accurate to 4 decimal places.

Answer 1