Choose a parent with children under age 18 in the United Sta…

Choose a parent with children under age 18 in the United States at random and ask, “How many nights a week out of seven does your family eat dinner together at home?” Call the response X for short. Based on a large sample survey, here is a probability model for the answer you will get What is P(X < 4)? _______

In a large population of college‑educated adults, the mean I…

In a large population of college‑educated adults, the mean IQ is 112 with standard deviation 25. Suppose 300 adults from this population are randomly selected for a market research campaign. The probability (rounded to three decimal places) that the sample mean IQ is greater than 115 is:  CrunchIt _______

A SRS of 25 recent birth records at the local hospital was s…

A SRS of 25 recent birth records at the local hospital was selected. In the sample, the average birth weight was x-bar = 119.6 ounces. Suppose the standard deviation is known to be σ = 6.5 ounces. Assume that in the population of all babies born in this hospital, the birth weights follow a Normal distribution, with mean μ. Based on the 25 recent birth records, the sampling distribution of the sample mean will be

A simple random sample of electronic components will be sele…

A simple random sample of electronic components will be selected to test for the mean lifetime in hours. Assume that component lifetimes are normally distributed with population standard deviation of {sd} hours. How many components must be sampled so that a 99% confidence interval will have margin of error of {m} hours? 50% 70% 80% 90% 95% 98% 99% 99.9% z* 0.674 1.036 1.282 1.645 1.960 2.326 2.576 3.291 Write only an integer as your answer.