mean, median, mode, MAD,

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mean, median, mode, MAD, box plots

• Review

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1 2 3 4 5
6 7 8 9
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1

• Name the two Measures of Center we have discussed

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1 Answer

• Mean
• Median

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2

• Name the three Measures of Spread we have
  discussed.

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2 Answer

• Range
• Interquartile range (IQR)
• Mean Absolute Deviation (MAD)

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3

• Find the mean, median and mode of the data
  displayed in the stem-and-leaf plot.

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3 Answer

• Mean 73.25
• Median 74
• Mode 63, 82, and 83

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4

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4 Answer
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5

• Heights of basketball players (in)
• 73, 67, 75, 81, 67, 75, 85, 69
• lower extreme ____
• upper extreme ____
• LQ/Q1 ____ median ____
• UQ/Q3 ____ range ____IQR ____
• Make a box plot to display the data.

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5 Answer

• Heights of basketball players (in)
• 73, 67, 75, 81, 67, 75, 85, 69
• lower extreme 67
• upper extreme 85
• LQ/Q1 68 median 74
• UQ/Q3 78 range 18 IQR 10

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6

• The IQR represents what percent of the data?
  _____
• What percent of the baseball players are shorter
  than 74 in? _____
• The median to the lower quartile represents what
  percent of the data? _____
• What is the IQR of the data? _____
• What is the range of the data? _____
• Suppose the tallest player was 80 in, instead of
  76 in. Would this be more likely to affect the
  range or IQR? Explain.

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6 Answer

• The IQR represents what percent of the data? 50
• What percent of the baseball players are shorter
  than 74 in? 75
• The median to the lower quartile represents what
  percent of the data? 25
• What is the IQR of the data? 8
• What is the range of the data? 12
• Suppose the tallest player was 80 in, instead of
  76 in. Would this be more likely to affect the
  range or IQR? Explain. The range, the higher
  number would make the range larger. It wouldnt
  affect the median.

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Math Test Scores Olive 98 92 88 92
95 Chris 88 86 93 88 90

• Find the mean absolute deviation of both
  students test scores.
• Who has a better test average?
• Who is the most consistent test taker? How do you
  know?

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7 Answer
Mean 465/5 93
Mean 445/5 89
Olives Test Scores Distance from mean
98 5
92 1
88 5
92 1
95 2
Chriss Test Scores Distance from mean
88 1
86 3
93 4
88 1
90 1
MAD 14/5 2.8
MAD 10/5 2

• Olive has a higher test average.
• Chris is the more consistent test-taker, because
  his MAD is smaller. This means that his test
  scores are closer to the mean.

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8

• Ten students were surveyed to find out how much
  weekly allowance they received. The following
  data was collected 8, 8, 6.50, 12, 12, 9,
  15, 15, 25, 45.
• mean _________________ median _____________
• Which measure of center is the most appropriate
  to describe the typical allowance for this group
  of students? Justify your reasoning.

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8 Answer

• Ten students were surveyed to find out how much
  weekly allowance they received. The following
  data was collected 8, 8, 6.50, 12, 12, 9,
  15, 15, 25, 45.
• mean 15.55 median 12
• Which measure of center is the most appropriate
  to describe the typical allowance for this group
  of students? Justify your reasoning.The median
  best represents the measure of center for this
  data, because it is closer to more of the data.
  Eight of the ten pieces of data fall below the
  mean.

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9

• Amandas test scores are 85, 93, 84, and 88. What
  does she need to score on the next test for her
  test average to be a 90?

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9 Answer

• Amandas test scores are 85, 93, 84, and 88. What
  does she need to score on the next test for her
  test average to be a 90?