# statistics

1. Determine whether the given source in the following scenario has the potential to create a bias in a statistical study.

Amounts of arsenic in samples of rice grown in Texas were measured by the Food and Drug Administration (FDA). Is there a potential to create bias?

2.A deadly disaster in the United States was the Triangle Shirtwaist Factory Fire in New York City. A population of 146 garment workers died in that fire.

Identify whether the given value is a __statistic__ or a __parameter__

3.The average (mean) atomic weight of all elements in the periodic table is 134.355 unified atomic mass units

Identify whether the given value is a __statistic__ or a __parameter__.

4.The Clerk of the US House of Representatives records the number of representatives present at each session.

Determine whether the data from a __discrete__ or __continuous__ data set.

5.When studying the relationship between lengths of feet and heights so that footprint evidence at the crime scene can be used to estimate the height of the suspect, a researcher records the exact lengths of feet from a large sample of random subjects

Determine whether the data from a __discrete__ or __continuous__ data set.

6.One study showed that for a recent period of 11 years, there was a strong correlation (or association) between the numbers of people who drowned in swimming pool and the amounts of power generated by nuclear power plants (based on data from the Centers for Disease Control and Prevention and the Department of Energy). Does this imply that increasing power from nuclear power plants is the cause of more deaths in swimming pools? Why or why not?

7.Determine whether the sampling method appears to be sound or is flawed. Briefly explain the reason.

Researchers at Yale University conduct a wide variety of clinical trials by using subjects who volunteer after reading advertisements soliciting paid volunteers.

8.In a study conducted by the Society for Human Resource Management, 347 human resource professionals were surveyed. Of those surveyed, 73% said that their companies conduct criminal background checks on all job applicants.

- What is the exact value that is 73% of the 347 survey subject?
- Could the result from part (a) be the actual number of survey subjects who said that their companies conduct criminal background checks on all job applicants? Why or why not?
- What is the actual number of survey subjects who said that their company conducts criminal background checks on all job applicants?
- Assume that 112 of the survey subjects are females. What percentage of those surveyed are females?

9.Find the range, variance, and standard deviation for the given sample data. Please make sure to show your work step by step. Listed below are prices in dollars for one night at different hotels located on Las Vegas Boulevard. How useful are the measures of variation for someone searching for a room?

212 77 121 104 153 264 195 244

10.“Who discovered penicillin: Sean Penn, William Penn, Penn Jillette, Alexander Fleming, or Louis Pasteur?” If you make a random guess for the answer to that question, what is the probability that your answer is the correct answer of Alexander Fleming?

11.In a recent year in the United States, 83,600 passenger cars rolled over when they crashed, and 5,127,400 passenger cars did not roll over when they crashed. The probability that randomly selected passenger cars did not roll over when they crashed is: ____. Is it unlikely for a car to roll over in a crash? ____ (yes or no).

12.A roulette wheel has 38 slots. One slot is 0, another is 00, and the others are numbered 1 through 36, respectively. You place a bet that the outcome is an odd number. Your probability of winning is: ____. The actual odds against winning is: ____.

13.In China, where many couples were allowed to have only one child, the probability of a baby being a boy was 0.545. Among six randomly selected births in China, the probability that at least one of them is a girl is ____.

14.Assume that random guesses are made for eight multiple choice questions on an SAT test, so that there are n=8 trials, each with probability of success (correct) given by p=0.20. Find the probability that the number x of correct answers is no more than two.

15.Assume that when adults with smartphones are randomly selected, 54% use them in meetings or classes (based on data from an LG Smartphone survey). If 12 adult smartphone users are randomly selected, find the probability that fewer than 3 of them use their smartphones in meetings or classes.

16.In a recent year, there were 333 murders in New York City. Find the mean number of murders per day, then use that result to find the probability that in a day, there are no murders.