Math3 - Study guides, Class notes & Summaries

1. Question: A dishwasher has a mean life of 11.5 years with an estimated standard deviation of 1.5 years ("Appliance life expectancy," 2013). Assume the life of a dishwasher is normally distributed. Find the number of years that the bottom 10% of dishwasher would last. Round answer to 2 decimal places. 2. Question: The size of fish is very important to commercial fishing. A study conducted in 2012 found the length of Atlantic cod caught in nets in Karlskrona to have a mean of 47.8 cm and a s...

1. Question: A coin is flipped 30 times. What is the probability of getting 15 or more heads? Round answer to 4 decimal places. 2. Question: It is known that 50% of adult workers have a high school diploma. If a random sample of 8 adult workers is selected, what is the probability that less than 6 of them have a high school diploma? 3. Question: If random variable X has a binomial distribution with n=9 and P(success) =p= 0.4, find the standard deviation of X. 4. Question: If random variable X...

1. Question: An instructor wants to compare spread (variation) of final grades of students in her online class and face-to-face class. The instructor selects 10 students randomly from each class and the following table shows the final grades of those students. See Attached Excel for Data. 2. Question: The lengths (in kilometers) of rivers on the South Island of New Zealand that flow to the Tasman Sea are listed below. Find the variance. See Attached Excel for Data. Use the Excel function to fin...

1. Question: A vacation resort rents SCUBA equipment to certified divers. The resort charges an up-front fee of $25 and another fee of $12.50 an hour. What is the dependent variable? 2. Question: Which of the following equations are linear? 3. Question: You are thinking about opening up a Starbucks in your area but what to know if it is a good investment. How much money do Starbucks actually make in a year? 4. Question: You move out into the country and you notice every Spring there are more ...

1. Question: An instructor wants to compare spread (variation) of final grades of students in her online class and face-to-face class. The instructor selects 10 students randomly from each class and the following table shows the final grades of those students. See Attached Excel for Data. 2. Question: The lengths (in kilometers) of rivers on the South Island of New Zealand that flow to the Tasman Sea are listed below. Find the variance. See Attached Excel for Data. Use the Excel function to fin...

1. Question: The least squares regression line for a data set is yˆ=5+0.3x and the standard deviation of the residuals is 0.4. Does a case with the values x = 3.3, y = 7.2 qualify as an outlier? 2. Question: The least squares regression line for a data set is yˆ=5+0.3x and the standard deviation of the residuals is 0.52. Does a case with the values x = -1.59, y = 5.78 qualify as an outlier? 3. Question: The following data represent the weight of a child riding a bike and the rolling distance...

1. Question: The population standard deviation for the height of college football players is 2.7 inches. If we want to estimate a 95% confidence interval for the population mean height of these players with a 0.65 margin of error, how many randomly selected players must be surveyed? 2. Question: The population standard deviation for the height of college basketball players is 2.9 inches. If we want to estimate a 99% confidence interval for the population mean height of these players with a 0.45...

1. Question: A dishwasher has a mean life of 11.5 years with an estimated standard deviation of 1.5 years ("Appliance life expectancy," 2013). Assume the life of a dishwasher is normally distributed. Find the number of years that the bottom 10% of dishwasher would last. Round answer to 2 decimal places. 2. Question: The size of fish is very important to commercial fishing. A study conducted in 2012 found the length of Atlantic cod caught in nets in Karlskrona to have a mean of 47.8 cm and a s...

1. Question: A large department store is curious about what sections of the store make the most sales. The manager has data from ten years prior that show 30% of sales come from Clothing, 25% Home Appliances, 18% Housewares, 13% Cosmetics, 12% Jewelry, and 2% Other. In a random sample of 550 current sales, 188 came from Clothing, 153 Home Appliances, 83 Housewares, 54 Cosmetics, 61 Jewelry, and 11 Other. At α=0.10, can the manager conclude that the distribution of sales among the departments ha...

1. Question: The population standard deviation for the height of college football players is 2.7 inches. If we want to estimate a 95% confidence interval for the population mean height of these players with a 0.65 margin of error, how many randomly selected players must be surveyed? 2. Question: The population standard deviation for the height of college basketball players is 2.9 inches. If we want to estimate a 99% confidence interval for the population mean height of these players with a 0.45...