Meet Poovizhi's Family
Five family members, one much shorter than the rest.
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One much shorter member pulls the family's average height down, but hardly moves the middle value.
Find the median for odd and even counts, spot outliers, and see how an outlier pulls the mean away from the median.
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Sort the data and pick the middle: that is the median.
Five family members, one much shorter than the rest.
One much shorter member pulls the family's average height down, but hardly moves the middle value.
Finding the median with 5 values and with 6 values.
Problem. Find the median height of each family. (Textbook p. 106)
Medians of the book's data sets.
Median of Poovizhi's family: 170, 173, 165, 118, 175?
One unusual value can drag the mean; the median barely moves.
A value that is very different from the rest is an outlier, like the 118 cm child.
Short stories read over the summer, with one reader of 40!
Problem. After summer vacation, 15 students wrote how many short stories they read: 6, 8, 5, 15, 3, 0, 2, 7, 12, 40, 0, 8, 1, 10, 5. Find the mean and median. Guess first: will the mean be more or less than the median? (Textbook pp. 107–108)
Find the mean and median of a week's newspaper pages.
Textbook p. 108, 'Are We on the Same Page?' Pages from Monday to Sunday: 16, 18, 20, 22, 26, 16, 10.
Sorted: 10, 16, 16, 18, 20, 22, 26. Median =
Total = , so the mean = 128 ÷ 7 ≈ (to 2 decimal places)
The mean and median are to each other, so the data is fairly balanced.