Cumulative AP Practice Test

You look at real estate ads for houses in Sarasota, FL. Many houses have prices from $200,000 to $400,000. The few houses on the water, however, have prices up to $15 million. Which of the following statements best describes the distribution of home prices in Sarasota?

• The distribution is more likely skewed to the left, and the mean is greater than the median

• The distribution is most likely skewed to the left, and the mean is less than the median

• The distribution is roughly symmetric with a few high outliers, and the mean is approximately equal to the median

• The distribution is most likely skewed right, and the mean is greater than the median

• The distribution is most likely skewed to the right, and the mean is less than the median

a child is 40 inches tall, which places her at the 90th percentile of all children of similar ages. The heights for children of this age form an approximately Normal distribution with a mean of 38 inches. Based on this information, what is the standard deviation of the heights of all children this age.

• 0.20 in

• 0.31 in

• 0.65 in

• 1.21 in

• 1.56 in

A large set of test scores has mean 60 and standard deviation 18. If each score is doubled, and then 5 is subtracted from the result, the mean and standard deviation of the new scores are:

• mean 115 and SD 31

• mean 115 and SD 36

• mean 120 and SD 6

• mean 120 and SD 31

• mean 120 and SD 36

For a certain experiment, the available experimental units are eight rats, of which four are female (F1, F2, F3, F4) and four are male (M1, M2, M3, M4). There are to be four treatment groups, A, B, C, and D. If a randomized block design is used with the experimental units blocked by gender, which of the following assignments of treatments is impossible?

• A: (F1, M1) B: (F2, M2) C: (F3, M3) D: (F4, M4)

• A: (F1, M2) B: (F2, M3) C: (F3, M4) D: (F4, M1)

• A; (F1, M2) B: (F3, F2) C: (F4, M1) D: (M3, M4)

• A: (F4, M1) B: (F2, M3) C: (F3, M2) D: (F1, M4)

• A: (F4, M1) B: (F1, M4) C: (F3, M2) D: (F2, M3)

For a biology project, you measure the weight in grams (g) and the tail length in millimeters (mm) of a group of mice. The equation of the least-squares regression line for predicting tail length from weight is:

predicted tail length = 20 + 3(weight)

Which of the following is NOT correct?

• The slope is 3, which indicates that a mouse's predicted tail length should increase by about 3 mm for each additional gram of weight.

• The predicted tail length of a mouse that weighs 38 grams is 134 millimeters

• By looking at the equation of the least-squares line, you can see that the correlation between eight and tail length is positive

• If you had measured the tail length in centimeters instead of millimeters, the slope of the regression line would have been 3/10 = 0.3

• Mice that have a weight of 0 grams will have a tail length of 20 mm

The figure shows a Normal density curve. Which of the following gives the best estimates for the mean and standard deviation of this Normal distribution?

• $\mu=200,\ \sigma=50$

• $\mu=200,\ \sigma=25$

• $\mu=225,\ \ \sigma=50$

• $\mu=225,\ \sigma=25$

• $\mu=225,\ \sigma=275$

The owner of a chain of supermarkets notices that there is a positive correlation between the sales of soda and the sales of ice cream over the course of the previous year. During seasons when sales of soda were above average, sales of ice cream also tended to bee above average. Likewise, during seasons when sales of soda were below average, sales of ice cream also tended to be below average. Which of the following would be a valid conclusion from these facts?

• Sales records must be in error. There should be no association between soda and ice cream sales.

• Evidently, for a significant proportion of customers of these supermarkets, drinking soda causes a desire for ice cream or eating ice cream causes a thirst for soda

• A scatterplot of monthly soda sales would show that a straight line describes the pattern in the plot, but it would have to be a horizontal line

• There is a clear negative association between soda sales and ice cream sales

• The positive correlation is most likely a result of the variable temperature; that is, as temperatures increase, so do both soda sales and ice cream sales.

Here are the IQ scores of 10 randomly chosen fifth-grade students. Which of the following statements is not true?

• The student with an IQ of 96 would be considered an outlier by the 1.5 x IQR rule.

• The 5-number summary of the 10 IQ scores is 96, 118, 123.5, 130, 145

• If the value 96 were removed from the data set, the mean of the remaining 9 IQ scores would be greater than the mean of all 10 IQ scores.

• If the value 96 were removed from the data set, the standard deviation of the remaining 9 IQ scores would be less than the standard deviation of all 10 IQ scores.

• If the value 96 were removed from the data set, the IQR of the remaining 9 IQ scores would be less than the IQR of all 10 IQ scores.

• I only

• II only

• III only

• II and III only

• I, II, and III

The General Social Survey (GSS) conducted by the National Opinion Research Center is a major source of data on social attitudes in the U.S. Once each year, 1500 adults are interviewed in their homes all across the country. The subjects are asked their opinions about many issues. The GSS begins by selecting a sample of counties from the 3000 counties in the country. The counties are divided into urban, rural, and suburban; a separate sample of counties is chosen at random from each group. This is a:

• Simple Random Sample

• Systematic Random Sample

• Cluster Sample

• Stratified Random Sample

• Voluntary Response Sample