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7-95.

Elvin found the box plot below in the school newspaper.  

Number of hours spent watching TV each week

Box Plot: x axis, scaled in fives, from 0 to 20. Left whisker: 0 to 3. Box: 3 to 10, vertical line at 5. Right whisker: 10 to 21.

  1. Based on the plot, what percent of students watch more than hours of television each week? 

    The box plot illustrates the quartiles of the data represented by the box in the middle.

    If the right side of the box over the hour represents the quartile of the data or the percentile, what percent of students watch more than hours of television each week?

    Added label, to right end of box, 75%.

  2. Based on the plot, what percent of students watch less than  hours of television each week?

    If the middle line of the box represents the middle half of all the data, what percent of students watch less than hours of television each week?

  3. Can Elvin use the plot to find the mean (average) number of hours of television students watch each week? If so, what is it? Explain your reasoning.

    Box plots are useful for representing the distribution of data, but they do not express any specific data other than the minimum and maximum.

    Since the mean would be the average number of hours that students watched television each week, could we calculate the mean with the information given or are specific data points necessary? Remember, mean and median are not the same.

    No, because individual data points are not given.

  4. Can he use the plot to find the median? If so, what is it? Explain your reasoning.

    The median is the middle half of all the data. Where on the box plot can this be represented? Does this make sense?

    Added label, to left end of box, 50%.