Researchers measured the length of time people spend brushing their teeth. For the 154 subjects in their study, the mean was 72.8 seconds with a standard deviation of 23. 5 seconds. Use this information with a 0.10 significance level to test the claim that the mean teeth brushing time was less than 80 seconds. Write your conclusion in plain English. (sentence)

In the Social Psychology course, you receive a score of 77 on the second exam. You are told that the standard deviation of the second exam is 8 and that your score is .75 standard deviations below the mean. a. What is the class mean of the second exam? b. Your friend scored a 70 on the second exam. How many standard deviations below the mean is your friend’s score?

A study of new home prices was conducted in a neighborhood of 2000 homes. The median price of a new home is reported to be $172,400 and the mean price is reported to be $196,000. describe the distribution of new home prices, explaining the relationship between the given median and mean. How many new homes cost more than $172,400?

Suppose that the mean score of a class of 34 students was 79. The 15 male students in the class had a mean score of 62. What was the mean score for the 19 female students? Mean Score for Female Students = preview answers

A study was commissioned to find the mean weight of the residents in certain town. The study found the mean weight to be 174 pounds with a margin of error of 7 pounds. Which of the following is a reasonable value for the true mean weight of the residents of the town?

Gabriel and Lucia took a road trip across the country. The room costs, in dollars, for their overnight stays are listed in the accompanying table. What does Chebyshev's theorem say about the number of the amounts that are within three standard deviations of the mean? Click the icon to view the room costs in dollars. There are at least observations that are within three standard deviations of the mean. (Round up to the nearest whole number.) Room Costs ($) 92 106 118 170 184 181 119 248 138 133 122 250 0 X

Suppose you are told that you scored  two standard deviations below the mean on a measure where the mean was 90 and the standard deviation was8. What is your score?

You have a sample of 48 randomly selected Vancouverites. On average (the sample mean), the people in your sample spent 425 hours eating food in 2020. The least time a person in the sample spent eating food in 2020 is 367 hours and the most time a person in the sample spent eating food in 2020 is 484 hours. What would be your best guess about the population standard deviation of the time a Vancouverite spent eating food in 2020? Give the number and explain (including assumptions you make about the population distribution).

Eye Color Based on a study by Dr. R Sorita at Indiana University, assume that 12% of us have green eyes. In a study of 650 people, it is found that 86 of them have green eyes. a. Find the probability of at least 86 people with green eyes among 650 randomly selected people. b. Is 86 people with green eyes significantly high?

Suppose that the mean score of a class of 34 students was 78. The 17 male students in the class had a mean score of 62. What was the mean score for the 17 female students?