The dotplot below displays the total number of miles that the 28 residents of one street in a certain community traveled to work in one five-day workweek. Which of the following is closest to the percentile rank of a resident from this street who traveled 85 miles to work that week?
A large simple random sample of people aged nineteen to thirty living in the state of Colorado was surveyed to determine which of the two MP3 players just developed by a new company was preferred. To which of the following populations can the results of this survey be safely generalized?
B) Only people aged nineteen to thirty living in the state of Colorado.
Janelle collected data on the amount of time in minutes each person in a large sample of customers spent in a local store. The data also included recording the gender of each customer. These data were used to generate the box plots shown below. Which of the following statements is true?
E) approximately half of the males in the sample of customers spent at least as much time in the store as any female in the sample of customers.
The probability of obtaining a head when a certain coin is flipped is about 0.65. Which of the following is closest to the probability that heads would be obtained 15 or fewer times when the coin is flipped 25 times?
A study was conducted using data collected on the birth weights of a random sample of 10 pairs of identical
C) Ho: uD= 0 and Ha: Uf -Us> UD
The buyer for an electronics store wants to estimate the proportion of defective wireless game controllers in a shipment of 5000 controllers
E) cluster random sample
A distribution of test scores is not symmetric. Which of the following is the best estimate of the z-score of the third quartile?
E) this z-score cannot be estimated from the information given
Sophomore, juniors, and senior students at a high school will be surveyed
A certain type of remote control car has a fully charged battery at the time of purchase
A) the probability that the running time of a randomly selected car of this type, before it requires recharging of the battery for the first time after its period of initial use, is between 75 minutes and 82.5 minutes.
Which of the following scatterplots could represent a data set with a correlation coefficient of r= -1?
A) linear, negative association
Publishers of a magazine wish to determine what proportion of the magazines 50,000 subscribers are pleased with their subscription
C) Mail surveys to 1,000 subscribers randomly selected from all subscribers.
An environmental scientist wanted to test the null hypothesis that an antipollution device for cars is not effective.
A) the scientist concludes that the antipollution device is effective when it actually is not.
A data set of test scores is being transformed by applying the following rule to each of the raw scores. Which of the following is not true
C) the range of transformed scores equals 3.5 ( the range of the raw scores) + 6.2
A random sample of 25 households from the Mountainview School District was surveyed. In this survey, data were collected on the age of the
D) 8 years old to less than 10 years old
Based on a random sample of 50 students, the 90 percent confidence interval for the mean amount of money students spend on lunch
D) 90% of all random samples of 50 students obtained at this high school would result in a 90% confidence interval that contains the true mean amount of money students spend on lunch.
Ten percent of all Dynamite mints candies are orange and 45 percent of all holiday mints candies are orange
D) 13.75 and 2.905
In a random sample of 60 shoppers chosen from the shoppers at a large suburban mall, 36 indicated that they has been to a movie
D) Two proportion z-test
Which of the following differences in cumulative relative frequencies gives the proportion of trees gives the proportion of trees that are 12 inches to 16 inches, inclusive, in diameter?
C) 0.726- 0.325
An outlier may be defined as a data point that is more than 1.5 times the IQR range below the lower quartile or is more than 1.5 times
The National Honor Society at Central High School plans to sample a random group of 100 seniors from all high school
D) increase the sample size
Ninety percent of the people who have a particular disease will have a positive result on a given diagnostic test
A recent survey concluded that the proportion of American teenagers who have a cell phone is 0.27. The true population
D) 0.29, square root of (0.29)(0.71)/1000
A marketing company wants to estimate the proportion of consumers in a certain region of the country who would react favorably to a new marketing campaign
Traffic data revealed 35 percent of automobiles traveling along a portion of an interstate highway were exceeding the legal speed limit
E) It cannot be determined from the information given
In a large school district, 16 of 85 randomly selected high school seniors play a varsity sport. In the same district, 19 of 67
The number of points, X scored in a game has the probability distribution below.
Each person in a random sample of adults indicated his or her favorite color. The results shown in the table below are reported by age group of the respondents
In a recent survey, 60 randomly selected married couples from the same town were asked the overall quality of living in their town on a scale of
A) husbands tended to rate the quality of living higher then their wives did.
A 90 percent confidence interval is to be created to estimate the proportion of television viewers in a certain area who favor the morning broadcast
B) the confidence interval would be 3 times as wide as the original confidence interval
A new restaurant is interested in determining the best time-temperature combination for roasting
E) the two cuts that are being roasted for each time-temperature combination are an example of replication.
A local real estate magazine used the median instead of the mean when it reported the SAT Score of the average student
A) the mean is affected by the skewness, whereas the median is not.
The director of a fitness center wants to examine the effects of two exercise classes (spinning and aerobics) on body fat percentage
C) the participants choice of which class to take
Raoul performed an experiment using 16 windup rubber band single-propeller airplanes. He wound up the propeller a different number of times
A) 0.0462 + (2.145)(0.01565)
A recent study was conducted to investigate the duration of time required to complete a certain manual dexterity task. The reported mean was 10.2 seconds
To determine whether employees at Site X have higher salaries,on average, than employees at Site Y of the same company do
C) At the 5% significance level, employees at Site X have a significantly higher mean salary than employees at site Y do.
The director of a technical school was curious about whether there is a relationship between students who complete one of the schools most popular
D) being a person who did not complete the program but completed more advanced studies are less likely than being a person who completed the program and completed more advanced studies.
On their birthdays, employees at a large company are permitted to take 60- minute lunch instead of the usual 30 minutes. Data were obtained from 10 randomly selected
E) given that the p-value is greater than 0.05, rejecting the null hypothesis and concluding that the mean time was not greater than 60 minutes.
A dog food company wishes to test a new high-protein formula for puppy food to determine whether is promotes faster weight gain than the existing formula
A) block on dog breed and randomly assign puppies to existing and new formula groups within each breed
A statistics student wants to compare the mean times needed to access flight information
D) The p-value is greater than 0.1 p; therefore there is no significant difference in mean search times on the two web sites.
The histogram below represents the data obtained