Math302 - Samenvattingen en Aantekeningen

1. Question: A manager wishes to see if the time (in minutes) it takes for their workers to complete a certain task is faster if they are wearing earbuds. A random sample of 20 workers' times were collected before and after wearing earbuds. Test the claim that the time to complete the task will be faster, i.e. meaning has production increased, at a significance level of α = 0.01 For the context of this problem, µD = µbefore−µafter where the first data set represents before earbuds and the...

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...

1. Question: "Number of times per week" is what type of data in the scenario? A study was done to determine the age, the number of times per week, and the duration (amount of time) of residents using a local gym in San Antonio, Texas. The first car in the parking lot was selected randomly, and then the resident of every eighth car in the lot around the gym was interviewed. 2. Question: What is the sampling method used in the following scenario? The barista at a local Starbucks wants to determ...

1. Question: A manager wishes to see if the time (in minutes) it takes for their workers to complete a certain task is faster if they are wearing earbuds. A random sample of 20 workers' times were collected before and after wearing earbuds. Test the claim that the time to complete the task will be faster, i.e. meaning has production increased, at a significance level of α = 0.01 For the context of this problem, µD = µbefore−µafter where the first data set represents before earbuds and the...

1. Question: A company manager believes that a person's ability to be a leader is directly correlated to their zodiac sign. He never selects someone to chair a committee without first evaluating their zodiac sign. An irate employee sets out to prove her manager wrong. She claims that if zodiac sign truly makes a difference in leadership, then a random sample of 210 CEO's in our country would reveal a difference in zodiac sign distribution. She finds the following zodiac signs for her random sa...

Which of the following equations are linear? 4y=8 A linear equation is a linear line. If a problem has a squared or a cubed term, it isn't linear. It is a quadratic equation. 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 independent variable? Time. The equation is Dollars = $12.5(hour) + $25 Dollars depends on how many hours you use the equipment for. Dollars is the dependent variab...

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...

Question 1 1 / 1 point 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?

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...