Q&A Hero

Related questions

Q: The following table represents the number of seconds that a particular web page took to load on an iPhone for 25 users along with the frequency in each class. Seconds to Load Number of Phone Users 0 to under 5 seconds 4 5 to under 10 seconds 7 10 to under 15 seconds 3 15 to under 20 seconds 10 20 to under 25 seconds 1 What is the approximate variance for the number of seconds that this web page took to load on the iPhone? A) 36.6 B) 38.2 C) 39.0 D) 40.7

---

Q: The following table represents the number of minutes that 20 airline passengers had to wait in order to pass through security along with the frequency in each class. Minutes with Security Number of Passengers 0 to under 10 minutes 4 10 to under 20 minutes 8 20 to under 30 minutes 5 30 to under 40 minutes 3 What is the approximate average number of minutes that a passenger waits to pass through security? A) 14.0 B) 15.5 C) 17.0 D) 18.5

---

Q: The average class size this semester in the business school of a particular university is 38.1 students with a standard deviation of 12.9 students. The z-score for a class with 21 students is ________. A) -1.33 B) 0 C) 0.80 D) 1.51

---

Q: The ________ identifies the number of standard deviations a particular value is from the mean of its distribution. A) coefficient of variation B) z-score C) median D) empirical rule

---

Q: The average math SAT score for incoming freshman at a particular college is 535 with a standard deviation of 60. The coefficient of variation for SAT scores at this school is ______. A) 11.2% B) 13.9% C) 15.6% D) 18.0%

---

Q: Comparing the consistency between two data sets when their means are very different is best done with the _______________. A) median B) z-score C) standard deviation D) coefficient of variation

---

Q: The following data represents the satisfaction scores from customers at a hotel on a 1-100 scale.7777818182838384848787899092929293939697Construct a stem and leaf display for this data, splitting the stems in half.

---

Q: A survey of 2,056 adults was asked how many books they typically read in a year. The following table shows the frequency distribution of the respondents. Response Frequency None 288 1-2 308 3-5 390 6-10 392 11 or more 678 Construct a chart that best displays this data.

---

Q: The following table shows a frequency distribution of the number of MacBook Air laptops sold per day at a particular Best Buy. Number of Laptops Frequency 0 2 1 5 2 3 3 8 4 5 5 2 What is the mean number of MacBook Air laptops sold per day? A) 2.6 B) 3.0 C) 3.5 D) 3.9

---

Q: The sample correlation coefficient measures the strength and direction of the linear relationship between two variables.

---

Q: A box-and-whisker plot displays the mean of the data set.

---

Q: The following table shows the average roundtrip airfare for domestic and international flights for each of three years. Year Domestic International 2009 $291 $710 2010 $302 $753 2011 $320 $863 Construct the type of chart that would be most appropriate if the goal was to compare the domestic and international airfare.

---

Q: The following table shows the number of points scored by the Green Bay Packers and the Detroit Lions of the National Football League over 15 recent seasons. Green Bay 560 388 461 419 435 301 298 424 442 398 390 353 357 408 422 Detroit 474 362 262 268 346 305 254 296 270 306 270 307 322 306 379 Use four classes, each with a class width of 100. Start classes with 201-300, 301-400, and so on, and construct a cumulative percentage polygon. What conclusions can you draw comparing these two teams?

---

Q: Steve's grade on a recent statistics exam was an 85 on a scale of 0-100. Based on this information, we can conclude that Steve's grade was in the 85th percentile in his class.

---

Q: The definition of the pth percentile (where p is any number between 1 and 100) is that at least p percent of the observations will fall below the value of interest.

---

Q: Chebyshev's Theorem only applies to bell-shaped curves that are relatively symmetrical.

---

Q: Data values that have z-scores above +1.0 or below -1.0 are categorized as outliers.

---

Q: In quality control settings, businesses prefer a larger standard deviation, which is an indication of more consistency in the process.

---

Q: Which one of the following statements is true for a left-skewed distribution? A) The mean is greater than the median. B) The mean is less than the median. C) The mean is greater than the mode. D) The mean is roughly equal to the median.

---

Q: The daily high temperature in Philadelphia over an eight-day period is shown below.6977708184866970The mode for this data set is ________.A) 69B) 70C) 69 and 70D) There is no mode for this data set.

---

Q: According to Consumer Reports, the average annual out-of-pocket costs for a root canal for Americans who do not have dental insurance is $1,201. Assume that this cost follows the normal distribution with a standard deviation of $118. Determine the interval of costs around the mean that includes 99.7% of the sample means.

---

Q: Assume that the amount of time that it takes an employee to service a car at an oil change facility follows the uniform probability distribution between 21 and 38 minutes. What is the probability that a randomly selected car will require between 25 and 35 minutes to service? A) 0.3216 B) 0.4133 C) 0.5882 D) 0.6425

---

Q: Assume that the amount of time that it takes an employee to service a car at an oil change facility follows the uniform probability distribution between 21 and 38 minutes. What is the probability that a randomly selected car will require more than 30 minutes to service? A) 0.1687 B) 0.2244 C) 0.3720 D) 0.4706

---

Q: Suppose the average tread-life of a certain brand of tire is 42,000 miles and that this mileage follows the exponential probability distribution. What is the probability that a randomly selected tire will have a tread-life between 30,000 and 50,000 miles? A) 0.1854 B) 0.2719 C) 0.5105 D) 0.6959

---

Q: Suppose the average tread-life of a certain brand of tire is 42,000 miles and that this mileage follows the exponential probability distribution. What is the probability that a randomly selected tire will have a tread-life of more than 40,000 miles? A) 0.1546 B) 0.2410 C) 0.3016 D) 0.3858

---

Q: Assume that the average talk time on an Apple iPhone is 20 hours and that this time follows the exponential probability distribution. What is the probability that a randomly selected iPhone will experience between 10 and 30 hours of talk time? A) 0.3834 B) 0.4650 C) 0.5219 D) 0.5875

---

Q: Assume that the average talk time on an Apple iPhone is 20 hours and that this time follows the exponential probability distribution. What is the probability that a randomly selected iPhone will experience more than 23 hours of talk time? A) 0.1969 B) 0.3166 C) 0.4258 D) 0.5916

---

Q: A discrete random variable that follows the Poisson distribution with a mean equal to λ has a counterpart continuous random variable that follows the ________ distribution with a mean equal to μ = 1/λ. A) exponential B) normal C) uniform D) discrete

---

Q: According to a Rasmussen Report survey, 4% of adults indicated that coffee ice cream was their favorite flavor. A random sample of 21 adults was selected. Use the Poisson distribution to approximate the binomial distribution to determine the probability that two or three adults from this sample would choose coffee ice cream as their favorite flavor.

---

Q: According to IDC, 3.6% of smartphones used a Windows operating system. A random sample of 30 smartphone users was selected. Use the Poisson distribution to approximate the binomial distribution to determine the probability that exactly two smartphones from this sample used a Windows operating system.

---