Feb 4th AP Stats

The following scatterplot describes the relationship between height (in cm) and foot length (also in cm) for 12 randomly selected students from the British Census @ Schools database. Which of the following is the best description of this relationship?

• There is some random variation, but otherwise height is directly proportional to foot length.
• There is a roughly linear relationship between height and foot length.
• There is a moderately weak, positive linear relationship between height and foot length.
• The relationship between height and foot length is linear, positive, and very strong.

Tags

CCSS.HSF.IF.B.4

Which of the following statements about the slope of the least-squares regression line is true? 

• It has the same sign as the correlation coefficient r.
• The square of the slope equals the proportion of the variation in the response variable that is explained by the explanatory variable.
• It is unitless.
• When the x-variable is 0, this is what the y-variable is predicted to be.

Tags

CCSS.HSS.ID.B.6

CCSS.HSS.ID.C.7

The point in the upper right hand corner of the scatterplot is

• not an outlier or an influential point
• not an outlier but an influential point
• an outlier and an influential point
• an outlier but not an influential point

Tags

CCSS.HSS.ID.A.3

CCSS.HSS.ID.B.6

The area under the standard normal curve corresponding to -0.2 < z < 2.03 is

• 0.5581

• 0.5686

• 0.3995

• 0.4100

The scores of the math portion of the SAT are approximately normal with a mean of 510 and a standard deviation of 42. Approximately what percent of students will score higher than 600?

• 0.9838

• 0.0162

• 0.0179

• 0.9821

The life span of ladybugs is approximately normally distributed with a mean of 18 months and a standard deviation of 2.5 months. Only about 5% of ladybuds will have a lifespan outside which interval?

• 15.5 to 23 months

• 15.5 to 20.5 months

• 13 to 23 months

• 10.5 to 25.5 months

95% of students who take the AP stats exam need between 186 and 214 minutes to complete it. What is the standard deviation of time students need to finish the exam? Assume times are normally distributed.

• 4.67 minutes

• 14 minutes

• 7 minutes

• 28 minutes

A college offers scholarships to students who score in the top 2% of students on an entrance exam. If the mean score on the exam is 176 and the standard deviation is 4, what is the minimum score a student would need to get a scholarship?

• 167.80

• 184.20

• 176.08

• 179.92

The correlation (r) between high school students' height (in inches) and weight (in pounds) for a large sample of students is found to be 0.3. If the weight measurements are converted to kg, what will be the resulting correlation?

(1 kg = 2.2 lbs)

• 0.3

• 0.66

• -0.3

• 0.136

Tags

CCSS.HSS.ID.C.8

A college professor asked his students how they feel about this statement: "I like math!" What proportion of women strongly agreed?

• 23.1%

• 57.1%

• 14.6%

• 26.7%