Probability and Statistics Pre Assessment

Probability and Statistics Pre Assessment Leave the first rating Students also studied Terms in this set (33) MathsProbability Save

AP Statistics: Probability (Unit Test ...

11 terms Nicholas_McGrath8 Preview Probabilities and Statistics 54 terms petradelolaPreview Stats exam 2 Probability 34 terms kendallbashPreview Inferen Teacher Hop In a class of 25 students, the following test scores were

obtained:

31, 46, 49, 52, 55, 67, 68, 68, 69, 69, 71, 73, 73, 75, 75, 78, 79,

82, 84, 84, 85, 87, 91, 92, 97

Which statement is true about this distribution?The distribution is skewed to the left.In a class of 25 students, the following test scores were

obtained:

51, 59, 59, 59, 67, 68, 68, 69, 69, 71, 73, 73, 75, 75, 78, 79, 82,

84, 85, 85, 87, 91, 92, 93, 93

A histogram of interval width 10 starting with the interval [50, 60] was constructed using the above data.Which statement is true about this distribution as depicted by the histogram?It is a unimodal symmetric distribution.In a class of 25 students, the following scores were

received on a quiz:

3, 3, 3, 3, 4, 4, 4, 4, 4, 5, 5, 6, 6, 6, 7, 7, 8, 8, 8, 8, 8, 9, 9, 9, 9

For this distribution, what is the most appropriate measure of central tendency?Either the mean or the median

The following 5-number summaries were obtained for

two distributions, A and B:

A 3.2 4.9 5.7 5.9 8.2

B 2.7 5.1 5.7 6.9 7.5

The distribution of A is skewed to the right, whereas the distribution of B is skewed to the left.How are the means of the two distributions related?The mean of A is higher than the mean of B.A study is conducted to determine if there is a difference in final exam scores in high school classrooms when different types of instruction are used. The two types of instruction included in the study are direct instruction and computer-based instruction.What are the explanatory (X) and response (Y) variables for this study?The type of instruction is the explanatory variable (X) and the test score is the response variable (Y).A store asked 350 of its customers whether they were satisfied with their service. The responses were also classified according to the gender of the customers.Satisfied Somewhat Satisfied Not Satisfied Total Male 60 60 50 170 Female 45 20 115 180 Total 105 80 165 350 If a person wanted to study whether the level of satisfaction is related to or affected by gender, what is the appropriate table of conditional probabilities?Satisfied Somewhat Satisfied Not Satisfied Total Male 35.35.3).40?male 25.0.1c.90% A local ice cream shop kept track of the number of cans of cold carbonated beverages it sold each day (Y) and the temperature that day (X) for 2 months during the summer.

The data are displayed in the following scatterplot:

Which statement describes the relationship between X and Y as it appears in the scatterplot?If the outlier were removed, r would increase.

The following table shows the age of a child in months (x) and the hours of sleep the child needs during nap time each day (y).Age Nap Time

• 8
• 5

6 3.25

• 3

12 2.5

18 2.25

24 2

36 1.5

The equation of the least squares regression line is y = -0.1351 x + 5.2787 y equals negative 0.1351 x plus 5.2787.Which two statements about the situation are true?There is a strong curvilinear relationship between the two variables. and The regression line predicts that an 11-month-old child would need 3.79 hour long naps.Data on the acceptance rates for professional programs at a university were collected over a five-year period. The

results are summarized in the following two-way table:

Number Accepted Number Not Accepted Total Men 625 807 1432 Women 650 1017 1667 From the table, it can be calculated that approximately 44% of male applicants were accepted, while 39% of female applicants were accepted. Similarly, the acceptance rates were calculated for both men and women for three of the university's professional programs and are summarized below.Percent Accepted Program Nursing Pharmacy Veterinary Medicine Men 34Q)% Women 40S3% Which statement describes this data?The variable "program" might be a lurking variable since the percentage of female applicants accepted is smaller than that of males overall, but when the program is considered, there is a reversal in the association.Over the past 50 years for a particular city there was a fairly strong positive linear relationship between its crime rate and the number of churches it has.Which two conclusions can be made from this?Choose 2 answers The variable "number of churches" can be used to only predict the "crime rate." and The population increase for the city over the past 50 years is a lurking variable that could influence both the crime rate and the number of churches to increase

Overall, Airline A completes 78% of its flights on time, while Airline B completes 68% of its flights on time. When examining the percentage of on-time flights for each airline based on the weather conditions of the flight

destinations, the given data is found:

Moderate Weather Severe Weather Airline A 79b% Airline B 82g% Which two statements are true about this scenario?Choose 2 answers This is an example of Simpson's paradox. and Weather conditions of the destination city is a lurking variable in this situation.A university wants to poll students regarding their opinions about a new policy. It is expected that men and women will have different views on the policy. Fifty-five percent of students at the university are men and 45% are women.Which sampling method should be used in this situation?Stratified sampling High school seniors in a certain city are to be surveyed regarding their post-high school plans.What would be a cluster sampling for this study?Obtain a list of all high schools in the city, choose four high schools at random, then survey all seniors at the four high schools.A small student group at a large high school wants to know the opinions of students regarding a new school policy.Which survey method is likely to produce the least amount of bias?Randomly select several classes from all classes at the school, then randomly select 10 students from each of these classes to survey.Each of 38 soccer teams has 14 players. A sample of 76 players is to be chosen as follows. Each team will be asked to place 14 cards with their players' names into a hat and randomly draw out two names. The two names from each team will be combined to make up the sample.Will this method result in a simple random sample of the 532 soccer players?No, because not every group of 76 players has the same chance of being selected.A researcher conducted a study of five randomly selected neighborhood adult cats. He reported the mean paw span to be 1.2 inches with a standard deviation of 0.2 inches.Which conclusion is valid for this data?The sum of the five cats paw spans was 6 inches.