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Stem and Leaf Plots, a la Shmoop. Kathryn R. Pillar lives on a plant stem.

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Don't ask us why, but she insists on arranging all her leaves into stem-and-leaf plot formations

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before she eats them. However, every time there's wind, her leaves

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get blown out of sequence. Here are the leaves, by number:

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Okay... before we get started... what in the world is a stem-and-leaf plot?

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It's basically a way of organizing data that shows the relationship of each value to the

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other values. To make a stem-and-leaf plot, create the "stem"

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by listing the digits with the largest place value to the left of a vertical line.

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In this case, we have the tens place...5 for 50, 4 for 40, 3 for 30, and 2 for 20.....

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The remaining digits... those in the ones place...

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...will be written to the right of the vertical line to create and organize the "leaves."

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Now that Kat has finished organizing, she decides that she wants to eat the middle leaf

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first. To find the middle leaf, also known as the

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median... ... we can simply cross out one number from

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the top and bottom until we reach the middle number.

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Unfortunately, Kat has found that the median lands between 47 and 45.

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She doesn't have a leaf labeled "46".. ...so she settles for the next best thing...

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the leaf with the average value. To find the average, or mean, we just have

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to add up the numerical values of all the leaves...

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... and divide by the total number of leaves. All of them added together equals 760. When

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we divide that by the total number of leaves... 18... it gives us roughly 42.2.

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Finally, Kat can lie down and try to sleep off her food coma.

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