What are the 4 numbers you need to know in order to fill in the Empirical Rule?
34, 13.5, 2.35, .15
A researcher wants to evaluate the effect of drinking coffee on sleep habits. He randomly chooses 100 people and asks whether they are coffee drinkers and how many hours of sleep they get each night.
Survey
What type of sampling method: Interview every 10th student who enters the school in the morning.
What is systematic?
What is the probability that a score is below a z-score of 0.73?
.7673
At a local high school, GPA's are normally distributed with a mean of 2.9 and standard deviation of 0.6. What percentage of students at the high school have a GPA between 2.3 and 3.5?
What is 68%
Population or Sample?
A quality control engineer is curious about the thickness of paint on a car at her factory. She randomly selects 30 points on the car and measures the paint thickness at each of those points.
What is sample?
A random sample of 150 Vermont High School seniors reveals that 60% plan to take the ACT this year. Use the margin of error to predict the actual proportion of seniors planning to take the exam.
Is the data quantitative or categorical?
Categorical
13.5%
Researchers visiting public high schools found that 75% of students used computers in their classroom work at least once a week. The researchers visited a total of 50 schools in 15 states.
Observational Study
What type of Sampling Method: Political webpages often allow readers to rate (if they want to) whether they strongly agree, agree, disagree, or strongly disagree with the President's decision on any given situation. This is a form of:
What is self-selected?
A sample of 121 high school seniors were surveyed on their level of school spirit on a scale of 0-100. The sample mean of this survey is 86. The known population standard deviation is 14 for all seniors in the class. Calculate the margin of error and, create an interval for the population mean?
What is [83.5, 88.5]
4.1 or higher
In your math class your teacher asks you to collect data on the approval rating of the president of the United States. You decided to ask the students in the cafeteria the following question "Do you approve of the way the president is handling his job?" This method of collection is an example of a ____________.
What is survey?
The average waist size for teenage males is 29 inches with a standard deviation of 2 inches.
If waist sizes are normally distributed, how many standard deviations away from the mean is a teenage male with a 33 inch waist.
What is -2
The weight of adult male beagles are normally distributed, with a mean of 25 pounds and a standard deviation of 3 pounds. Find the probability that the weight of a randomly selected male beagle is between 23 and 25 pounds.
What is 0.2486?
What is the z-score that corresponds to 80.23% of the data to the left?
.85