Exam 3: Describing, Exploring, and Comparing Data

In a data set with a range of 55.4 to 105.4 and 400 observations, there are 276 observations with values less than 86. Find the percentile for 86.

A male student of the author has a measured pulse rate of 52 beats per minute. According to a National Center for Health Statistics data set, males have a mean pulse rate of 67.3 beats per minute and a standard deviation of 10.3 beats per minute. Determine whether the student's pulse rate is significantly low or high by determining the difference between the student's pulse rate and the mean pulse rate of males and how many standard deviations that difference represents by calculating the z score. Consider usual pulse rates to be within 2 standard deviations of the mean.

Find the indicated measure. -The test scores of 32 students are listed below. Find $\mathrm { P } _ { 46 }$ 32 37 41 44 46 48 53 55 56 57 59 63 65 66 68 69 70 71 74 74 75 77 78 79 80 82 83 86 89 92 95 99

Find the variance for the given sample data. Round your answer to one more decimal place than the original data. 7 7 2 5 1

Solve the problem. -A student earned grades of B, B, A, C, and D. Those courses had these corresponding numbers of credit hours: 4, 5, 1, 5, 4. The grading system assigns quality points to letter grades as follows: A = 4, B = 3, C = 2, D = 1, and F = 0. Compute the grade point average (GPA) and round the result to two decimal places.

Find the mode(s) for the given sample data. - 7.35 7.41 7.56 7.35 7.88 7.99 7.62

Find the standard deviation for the given sample data. Round your answer to one more decimal place than is present in the original data. - 153 133 256 155 242 233 264 182 128

Solve the problem. -A class of sixth grade students kept accurate records on the amount of time they spent playing video games during a one-week period. The times (in hours) are listed below: 25.7 13.6 9.2 14.2 18.6 30.4 19.8 14.0 24.6 24.1

Find the number of standard deviations from the mean. Round your answer to two decimal places. -Mario's weekly poker winnings have a mean of $353 and a standard deviation of $67. Last week he won $185. How many standard deviations from the mean is that?

Find the standard deviation for the given sample data. Round your answer to one more decimal place than is present in the original data. -Listed below are the amounts of time (in months) that the employees of a restaurant have been working at the restaurant. 2 3 6 17 22 40 54 73 101 122

Solve the problem. -The geometric mean is often used in business and economics for finding average rates of change, average rates of growth, or average ratios. Given n values (all positive), the geometric mean is the nth root of their product. The average growth factor for money compounded at annual interest rates of 34%, 26%, 24%, and 22% can be Found by computing the geometric mean of 1.34, 1.26, 1.24, and 1.22. Find that average growth factor.

Find the median for the given sample data. -A store manager kept track of the number of newspapers sold each week over a seven-week period. The results are shown below. 81 71 202 113 269 248 242 Find the median number of newspapers sold.

Construct a boxplot for the given data. Include values of the 5-number summary in all boxplots. -The test scores of 40 students are listed below. Construct a boxplot for the data set. 25 35 43 44 47 48 54 55 56 57 72 73 74 76 77 77 78 79 80 81 81 828385 89 92 93 94

Find the mode(s) for the given sample data. -The speeds (in mi/h) of the cars passing a certain checkpoint are measured by radar. The results are shown below. 41.8 41.4 44.4 43.7 45.3 45.3 41.4 40.0 47.8 43.7 41.8 40.0 43.7 39.7 41.4 44.1 44.1 44.4 48.8 41.8

Provide an appropriate response. -For data which are heavily skewed to the right, P10 is likely to be closer to the median than P90. True or false?

Solve the problem. -When data are summarized in a frequency distribution, the median can be found by first identifying the median class (the class that contains the median). We then assume that the values in that class are evenly Distributed and we can interpolate. This process can be described by median $= ($ lower limit of median class $) + ($ class width $) \left( \frac { \frac { \mathrm { n } + 1 } { 2 } - ( \mathrm { m } + 1 ) } { \text { frequency of median class } } \right)$ where $\mathrm { n }$ is the sum of all class frequencies and $\mathrm { m }$ is the sum of the class frequencies that precede the median class. Use this procedure to find the median of the frequency distribution below: Score Frequency 50-59 21 60-69 24 70-79 22 80-89 16 90-99 17

Solve the problem. Round results to the nearest hundredth. -The mean of a set of data is -2.91 and its standard deviation is 3.88. Find the z score for a value of 2.80.

The normal monthly precipitation (in inches) for August is listed for 20 different U.S. cities. Find the mean monthly precipitation. 3.5 1.6 2.4 3.7 4.1 3.9 1.0 3.6 4.2 3.4 3.7 2.2 1.5 4.2 3.4 2.7 0.4 3.7 2.0 3.6

Find the percentile for the data value. - Data set: 122 134 126 120 128 130 120 118 125 122 126 136 118 122 124 119; data value: 128

Scores on the SAT test have a mean of 1518 and a standard deviation of 325. Scores on the ACT test have a mean of 21.1 and a standard deviation of 4.8. Which of the following choices is not true?