Warmup Bob looked at online ads and wanted to visit 9 dealers on Staurday. The number of miles for each dealer from his house is the following: 3 12 8 6 8 31 4 7 10 a) Calculate the mean distance from his house b) Calculate the median distance from his house c) Is the data skewed? Explain d) What is the range of the distances? e) What is the IQR? f) What is the mode?

5-3 USING GRAPHS TO UNDERSTAND DATA Banking 2/28/2019 5-3 USING GRAPHS TO UNDERSTAND DATA OBJECTIVES ”A picture is worth a thousand words” Create a frequency distribution from a set of data. Use box-and-whisker plots and stem-and-leaf plots to display information. Chapter 1

Banking 2/28/2019 Today’s Standard MMFD2. Students will use data displays including bar graphs, line graphs, stock bar charts, candlestick charts, box and whisker plots, stem and leaf plots, circle graphs, and scatterplots to recognize and interpret trends related to the stock market, retirement planning, insurance, car purchasing, and home rental or ownership. Chapter 1

Example 1 Jerry wants to purchase a car stereo. He found 33 ads for the stereo he wants and arranged the prices in ascending order: $540 $550 $550 $550 $550 $600 $600 $600 $675 $700 $700 $700 $700 $700 $700 $700 $750 $775 $775 $800 $870 $900 $900 $990 $990 $990 $990 $990 $990 $1,000 $1,200 $1,200 $1,200 He is analyzing the prices, but having trouble because there are so many numbers. Draw a stem-and-leaf plot to display the values graphically

Draw the stem-and-leaf plot here. Example 1 Draw the stem-and-leaf plot here. Find the number of car stereos selling for less than $800.

Find the median of the car stereos prices from Example 1. Jerry decides he is not interested in any of the car stereos priced below $650 because they are in poor condition and need too much work. Find the median of the data set that remains after those prices are removed.

EXAMPLE 3 Rod was doing Internet research on the number of gasoline price changes per year in gas stations in his county. The numbers were: 19, 26, 39, 40, 57, 64, 72, 17, 26, 39, 56, 64, 13, 23, 39, 55, 63, 12, 20, 39, 55, 11, 38, 54, 11, 36, 52, 33 Draw a stem-and-leaf plot. What is the median of this distribution?

CHECK YOUR UNDERSTANDING Find the range and the upper and lower quartiles and the IQR for the stem-and-leaf plot from Example 3.

EXAMPLE 4 Used car dealers do not always have good reputations. A study of dealers in the county measured the percent of customers who were satisfied and the results are shown using this stem-and-leaf plot. What is the median of this distribution? Find the range, the lower and upper quartiles and the IQR

EXAMPLE 5 Rod, from Example 3, found another graph called a box-and-whisker plot, or boxplot. It is shown below. Find the median, range and interquartile range of distribution using the boxplot. What percent of the gas stations had 55 or fewer price changes?

EXAMPLE 6 The following box-and-whisker plot gives the purchase prices of the cars of 114 seniors at West High School. Find the median, range and interquartile range of distribution using the boxplot. What percent of the cars cost more than $5,200?

EXAMPLE 7 Jerry is looking to purchase a set of used chrome wheels for his SUV. He found 23 ads for the wheels he wants online and in the classified ads of his local newspaper and arranged the prices in ascending order, which is given below. $350 $350 $350 $420 $450 $450 $500 $500 $500 $500 $600 $700 $725 $725 $725 $725 $725 $775 $775 $800 $825 $825 $850 Draw a box-and-whisker plot for the data.

EXAMPLE 8 The following represents the commute (in miles) for some teachers at Osborne: 2, 3, 5, 5, 7, 8, 8, 8, 9, 11, 11, 12, 13, 13, 14, 16, 17, 17, 22, 23, 23, 28, 31, 33, 40 Draw a box-and-whisker plot for the data.