Blog

A machine is supposed to fill bags with 19 ounces of candy. The manager of a candy factory wants to be sure that the machine does not underfill or overfill the bags. They select a random sample of 75 bags and find the mean weight of the bags is 19.28 ounces. At

A researcher wants to estimate the average amount of sleep college students get per night within 15 minutes (0.25 hour) of the population mean. What is the minimum sample size they would need to build a 95% confidence interval? Assume

Watch each prefix to the correct definition or description.

A manufacturer of tablet computers claims that their average battery life while watching videos is at least 11.5 hours. A random sample of 20 tablets are taken and they have a mean battery life while watching videos of 11.07 hours with a standard deviation of 1.097 hours. Assume battery life while watching videos is normally distributed. Write the null and alternative hypothesis for this hypothesis test. Check that the appropriate conditions are met and calculate the appropriate standardized test statistic. Assume the p-value is 0.0479 and

Deep breathing is called ____________________ and more shallow breathing is called __________________.

A random sample of 500 Douglas fir trees has a mean height of 112.3 ft. Construct and interpret a 90% confidence interval for the mean height of Douglas fir trees. Assume

A researcher is studying the average life span of hummingbirds. Their hypotheses are:

Connecticut is located between Boston and New York, so most baseball fans in the state typically root for either the Yankees or the Red Sox. In a recent survey of 803 randomly selected fans in Connecticut, 44% said their favorite team was the Yankees. Construct and interpret a 95% confidence interval for the proportion of baseball fans in Connecticut who say their favorite team is the Yankees.

Stress management can occur through various methods, but which one is the best?

Stress management can occur through various methods, but which one is the best?