Questions from Statistics Principles

Q: Suppose you wish to determine if the mean IQ of students on

Suppose you wish to determine if the mean IQ of students on your campus is different from the mean IQ in the general population, 100. To conduct this study, you obtain a simple random sample of 50 stu...

Q: An investigator with the Food and Drug Administration wanted to determine whether

An investigator with the Food and Drug Administration wanted to determine whether a typical bag of potato chips contained less than the 16 ounces claimed by the manufacturer.

Q: A researcher wanted to estimate the average length of time mothers who

A researcher wanted to estimate the average length of time mothers who gave birth via Caesarean section spent in a hospital after delivery of the baby.

Q: An official with the Internal Revenue Service wished to estimate the proportion

An official with the Internal Revenue Service wished to estimate the proportion of high-income (greater than $100,000 annually) earners who under-reported their net income (and, therefore, their tax l...

Q: According to the Pew Research Center, 55% of adult Americans

According to the Pew Research Center, 55% of adult Americans support the death penalty for those convicted of murder. A social scientist wondered whether a higher proportion of adult Americans with at...

Q: In 2014, of the 37 million borrowers who have outstanding student

In 2014, of the 37 million borrowers who have outstanding student loan balances, 14% have at least one past due student loan account. A researcher with the United States Department of Education be...

Q: Researchers measured regular testosterone levels in a random sample of athletes and

Researchers measured regular testosterone levels in a random sample of athletes and then measured testosterone levels prior to an athletic event. They wanted to know whether testosterone levels increa...

Q: A simple random sample of size n = 19 is drawn from

A simple random sample of size n = 19 is drawn from a population that is normally distributed. The sample mean is found to be 0.8, and the sample standard deviation is found to be 0.4. Test whether th...

Q: A simple random sample of size n = 200 individuals with a

A simple random sample of size n = 200 individuals with a valid driver’s license is asked if they drive an American-made automobile. Of the 200 individuals surveyed, 115 responded that they drive an A...

Q: The Gallup Organization asked 1050 randomly selected adult Americans age 18 or

The Gallup Organization asked 1050 randomly selected adult Americans age 18 or older who consider themselves to be religious, “Do you believe it is morally acceptable or morally wrong [rotated] to...