Stats final

weight of adult male grizzly bears living in the wild in the continental United States is approximately normally distributed with a mean of 500 pounds in a standard deviation of 50 pounds the weight of adult female grizzly bears approximately normally distributed with a mean of 300 pounds and a standard deviation of 40 pounds approximately. What would be the weight of a female grizzly bear with the same standardized Z score as a male grizzly bear with a

324 pounds

The five-number summary for a data set is given by min = 5, Q1 = 18, median = 20, Q3 = = 40, max = 75. If you wanted to construct a boxplot for the data set that would show outliers, if any existed, what would be the maximum possible length of the right-side "whisker"?

33

The number of unbroken charcoal briquets in a 20-pound bag filled at the factory follows a Normal distribution with a mean of 450 briquets and a standard deviation of 20 briquets. The company expects that a certain number of the bags will be underfilled, so the company will replace for free the 5% of bags that have too few briquets. What is the minimum number of unbroken briquets the bag would have to contain for the company to avoid having to replace the bag for free?

418

The country with a literacy rate of 49% is closest to which of the following percentiles?

6th

A candy company produces individually wrapped candies. The quality control manager for the company believes that the weight of the candies is approximately normally distributed with mean 720 milligrams (mg). If the manager's belief is correct, which of the following intervals of weights will contain the largest proportion of the candies in the distribution of weights?

700 mg to 740 mg

The distribution of heights of 6-year-old girls is approximately normally distributed with a mean of 46.0 inches and a standard deviation of 2.7 inches. Aliyaah is 6 years old, and her height is 0.96 tandard deviation above the mean. Her friend Jayne is also 6 years old and is at the 93rd percentile of the height distribution. At what percentile is Aliyaah's height, and how does her height compare to Jayne's height?

Aliyaah's height is at the 83rd percentile of the distribution, and she is shorter than Jayne.

A 100-question multiple-choice history exam is graded as number correct minus 1/4 number incorrect, so scores can take values from -25 to +100. Suppose the standard deviation for one class's results is reported to be -3.14. What is the proper conclusion?

An error was made in calculating standard deviation.

Professor James gave the same test to his three sections of statistics students. On the 35-question test, the highest score was 32 and the lowest was 15. Based on the information displayed in the boxplots above, which of the following statements is true?

At least 50% of the scores in section 3 are higher than all of the scores in section 1.

The overall shape of this distribution is

Clearly skewed to the left

A financial analyst determines the yearly research and development investments for 50 blue chip companies. She notes that the distribution is distinctly not bell-shaped. If the 50-dollar amounts are converted to z-scores, what can be said about the standard deviation of the 50 z-scores.

It equals 1.

Heights, in inches, for the 200 graduating seniors from Washington Hihg School are summarized in the frequency table below. Which of the following statements about the median height is true?

It is greater than or equal to 60 inches but less than 66 inches.

A large company is interested in improving the efficiency of its customer service and` decides to examine the length of the business phone calls made to clients by its sales staff. Here is a cumulative relative frequency graph from data collected over the past year. According to the graph, the shortest 80% of calls will take how long to complete?

Less than 10 min (length of phone call min.)

The mean of this distribution (don't try to find it) will be

Less than the median

Qu estions 3-5 refer to the following graph. Here is a dotplot of the adult literacy rates in 177 countries in a recent year, according to the United Nations. For example, the lowest literacy rate was 23.6%, in the African country of Burkina Faso. Mali had the next lowest literacy rate at 24.0%.

Literacg rate (%) *higher at 100%*

The kelvin is a unit of measurement for temperature; 0 K is absolute zero, the temperature at which all thermal motion ceases. Conversion from Fahrenheit to Kelvin is given by K = 5/9 (F − 32) + 273. The average daily temperature in Monrovia, Liberia is 78.35℉ with a standard deviation of 6.3℉. If a scientist converts Monrovia daily temperatures to the Kelvin scale, what will be the new mean and standard deviation?

Mean, 298.75 K; standard deviation 3.5 K

It is estimated the 56 percent of Americans have pets. However, favorite pet of choice differs by geographic location and by pet of choice. The results are summarized in the following segmented bar chart. Which of the following is an incorrect conclusion?

More pet owners in the South than in the North answered "Other."

Zucchini weights are approximately normally distributed with mean 0.8 pound and standard deviation 0.25 pound. Which of the following shaded regions best represents the probability that a randomly selected zucchini will weigh between 0.55 pound and 1.3 pounds?

Mu + 2(SD) to the right

The age distribution for a particular debilitating disease has a mean greater than the median. Which of the following graphs most likely illustrates this distribution?

Skewed right, greater towards the beginning (10-20)

A school is having a contest in which students guess the number of candies in a jar. The student whose guess is the closest to the correct number of candies in the jar wins a prize. The number of candies guessed by male and female students is shown in the back-to-back stemplot below. Which of the following statements is true about the distribution of guesses?

The distributions of guesses for male and female students are both skewed to the left.

The number of hurricanes reaching the East Coast of the United States was recorded for each of the last ten decades by the National Hurricane Center. Summary measures are shown below. Min = 12 Max = 24 1.5 IQ R Rule Lower quartile = 15 Upper quartile = 18 Median = 16 n = 10 Which of the following statements is true?

The largest observation is 24 and it is an outlier. No other observations in the data set could be outliers.

Height, in meters, is measured for each person in a sample. After the data are collected, all the height measurements are converted from meters to centimeters by multiplying each measurement by 100. Which of the following statistics will remain the same for both units of measure?

The z-scores of the height measurements

The following are the graphs of three normal curves and three cumulative distribution graphs: Which normal curve corresponds to which cumulative curve?

X and 1, Y and 2, Z and 3