Chapter 5 Review!!!

1. In 1995 The Educational Testing services adjusted the scores of SAT tests. Before ETS re-centered the SAT Verbal test, the MEAN of all test scores was 450.

A) How would adding 50 points to each score affect the MEAN A) How would adding 50 points to each score affect the MEAN? State an exact value for the mean

The MEAN would increase to 500! ANSWER: The MEAN would increase to 500!

The standard deviation was 100 points The standard deviation was 100 points. What would the standard deviation be after adding 50 points?

ANSWER: The standard deviation would not change. It is still 100 points.

Suppose we drew box plots of tests takers’scores a year before and a year after the recentering. How would the boxplots of the two years differ?

ANSWER: The two boxplots would look nearly identical ANSWER: The two boxplots would look nearly identical. The shape of the distribution would remain the same, but the later one would be shifted 50 points higher.

A company manufactures wheels for in-line skates A company manufactures wheels for in-line skates. The diameters of the wheels have a mean of 3 inches and a standard deviation of 0.1 inches. Because so many of their customers use the metric system, the company decided to report their production statistics in millimeters. 1 inch = 25.4 mm

What is the mean wheel diameter in millimeters?

ANSWER: 3 • 25.4 = 76.2mm

What is the standard deviation of the wheel diameter in millimeters?

ANSWER: 0.1•25.4=2.54mm

Which of the statistics would NOT change: Q1 IQR MAX

ANSWER: They would ALL change!!!

Roller coasters are a thrill ride in many amusement parks in the world Roller coasters are a thrill ride in many amusement parks in the world. And thrill seekers want a roller coaster that goes fast! There are two main typeof roller coasters: those with wooden tracks and those with steel tracks. DO they typically run at different speeds? Here are the boxplots.

Overall ________ roller coasters are slower than ________ roller coasters.

Overall WOODEN-TRACK roller coasters are slower than STEEL TRACK roller coasters.

In fact, the fastest half of the steel roller coasters are faster than ______% of the wooden roller coasters.

In fact, the fastest half of the steel roller coasters are faster than 75% of the wooden roller coasters.

The shape of the Steel track coasters is ___________ while the shape of the wooden track coasters is ________.

The shape of the Steel track coasters is SKEWED RIGHT WITH A HIGH OUTLIER while the shape of the wooden track coasters is ROUGHLY SYMMETRICAL.

The range of the speeds among steel roller coasters is _____________ than the range of speeds of wooden roller coasters.

The range of the speeds among steel roller coasters is LARGER than the range of speeds of wooden roller coasters.

Find the values for the upper and lower walls and determine if any of the scores are outliers…. 37, 45, 50, 11, 33, 49, 102, 29

ANSWER Q3 = 49.5 and Q1 = 31 so IQR = 18.5 18.5 x 1.5 = 27.75 Lower wall : 31 – 27.75 = 3.25 Upper Wall: 49.5 + 27.75 = 77.25 OUTLIER: 102

A) Which group had the worst recall and what is it A) Which group had the worst recall and what is it? b) Which group has the lowest median age and what is it?

A) Which group had the worst recall and what is it A) Which group had the worst recall and what is it? b) Which group has the lowest median age and what is it?

C) Which group has the smallest range of items recalled and what is it C) Which group has the smallest range of items recalled and what is it? d) State the shape of the high caffeine group e) Which group has the highest IQR?

C) Which group has the smallest range and what is it C) Which group has the smallest range and what is it? d) State the shape of the high caffeine group e) Which group has the highest IQR?

Turn to pages102 and 103 right now in your book and read for the next five minutes. Everything you need to know for your test tomorrow is mentioned on these pages! STUDY! Test is 47 points.