CP Statistics Chap 4-5 Review

Looking at this back-to-back stem and leaf plot, what can you conclude about the cars studied?

• The cars got about the same gas mileage in the city and on the highway.

• The cars that got the higher gas mileage must be smaller.

• The average gas mileage in the city is higher than on the highway.

• The average gas mileage on the highway is higher than in the city.

Which conclusion about the box and whisker plots is not true?

• The median score in 1^st period is lower than the median score in 2^nd period.

• The 3^rd quartile for both classes are both near 90.

• 1^st period scores have a smaller IQR

• The median in 1^st period is the same as quartile 1 in 2^nd period.

On one test your class achieved an average grade of 72 with a standard deviation of 8 points.

If you earned a 96, what’s your z-score?

• -3

• 3

• 7.2

• 87

On one test your class achieved an average grade of 72 with a standard deviation of 8 points.

Your best friend got a 76. What’s her z-score?

• -0.5

• 0.5

• 1.2

• 67

On one test your class achieved an average grade of 72 with a standard deviation of 8 points.

What test grade has a z-score of 1.5?

• -60

• 12

• 60

• 84

On one test your class achieved an average grade of 72 with a standard deviation of 8 points.

The teacher calls home whenever student’s z-score is worse than -2.0. What grades earn you that phone call?

• above 56

• below 56

• above 88

• below 88

A TV weatherman’s end-of-year analysis of the local weather showed that among all the years for which records had been kept, the past year’s average temperature had a z-score of 2.8. What does that mean?

• The past year’s average temperature was 2.8 degrees higher than the historical mean

• The past year’s average temperature was 2.8 standard deviations above the historical mean.

• The past year’s average temperature was 2.8% higher than the historical mean.

• The past year’s temperatures had a standard deviation of 2.8 degrees.

An incoming freshman took her college’s placement exams in French and math. In French, she scored 82 and in math 86. The overall results on the French exam had a mean of 72 and a standard deviation of 8, while the mean math score was 68, with a standard deviation of 12. On which exam did she do better compared to other freshmen?

• French

• Math

• The two tests ties for best

• She doesn’t care because she got a great job at Amazon.

Which is not among the First Three Rules for Working with Normal Models?

• Make a picture

• Start putting numbers in your calculator before making a picture

• Make a picture

• Make a picture

What is the rule we can use to describe a Normal distribution?

• 68-95-99.7 Rule

• 65-95-99.7 Rule

• 68-88-98 Rule

• 68-95-98 Rule