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Lesson 1.6 %u2022 Measuring Center 65 We will show you how to calculate measures of center (and variability) using technology in Lesson 1.7. SOLUTION: (a) The mean is pulled toward the long tail in this right-skewed distribution. Also, the dwelling with a lead level of 104 ppb in the water is an outlier that inflates the mean but does not affect the median as much. (b) The median lead level of 3 ppb better summarizes the center of the distribution. The mean of 7.31 ppb does not reflect the typical lead level in the water%u2014only 15 of the 71 dwellings in the sample had lead levels this high or higher. FOR PRACTICE TRY EXERCISE 17. YO U R TU R N LE SSO N 1.6 Why are there so few chips in the bag? Have you ever noticed that bags of chips seem to contain lots of air and not enough chips? A group of chip enthusiasts collected data on the percentage of air in each of 14 popular brands of chips. Here are their data, along%u00a0with a dotplot: 72 Brand Percent air Brand Percent air Cape Cod 46 Popchips 45 Cheetos 59 Pringles 28 Doritos 48 Ruffles 50 Fritos 19 Stacy%u2019s Pita Chips 50 Kettle Brand 47 Sun Chips 41 Lays 41 Terra 49 Lays Baked 39 Tostitos Scoops 34 0 10 20 30 40 50 60Percent air 1. Find and interpret the median. 2. Calculate the mean percent air in these bags of chips. 3. Which measure of center%u2014the median or the mean%u2014better describes a typical percentage of air in these bags of chips? Explain your answer. Ann Heath Lesson 1.6 W H AT D I D Y O U L E A R N ? LEARNING TARGET EXAMPLE EXERCISES Find and interpret the median of a distribution of quantitative data. p. 61 9%u201312 Calculate the mean of a distribution of quantitative data. p. 62 13%u201316 Compare the mean and median of a distribution, and choose the more appropriate measure of center in a given setting. p. 64 17%u201320 %u00a9 Bedford, Freeman & Worth Publishers. For review purposes only. Do not distribute.