The Time Required for Ten Children to Learn a Particular

The time required for ten children to learn a particular motor skill was recorded as 9, 15, 23, 20, 16, 15, 24, 18, 10, and 20 minutes.
a. Find the mean time to learn this task.
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b. Find the median time to learn this task.
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c. Based on the values of the mean and median in parts (a) and (b) above, are the measurements symmetric or skewed?
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Explain.
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