Jamie 19 F Leilani 20 F Reid 15 M Use the approaches below to determine how accurately the class predicted when 30 seconds has passed. (a) Find the mean, median and range for the predictions of when 30 seconds has passed for the class data. Describe how accurate the predictions were. How many of the predictions are within 5 seconds of 30 seconds? How many predictions are below 30 seconds? How many are above? (b) Produce a box plot of the prediction times. Describe the distribution of prediction times. (c) Find the mean, median and range for the predictions made by boys and for the predictions made by girls. Compare the accuracy of the predictions made by these two groups. (d) Produce separate box plots for the predictions made by the boys and girls. Compare the distributions. Answers: (a) The mean is 399/15 = 26.6 seconds. The ordered times are: 14 15 18 19 19 20 21 26 32 33 34 35 36 37 40 The median prediction is 26 seconds and the range is seconds. Eight students had a prediction that was less than 30 seconds and seven had a prediction that was more than 30 seconds. Five of the predictions are within 5 seconds of 30 seconds (26, 32, 33, 34 and 35). Interpretations: On average the predictions are about 3 or 4 seconds less than 30 seconds and the difference between the lowest and highest predictions is 26 seconds. (b) The box plot is shown below: The distribution is roughly symmetric. (c) The results are shown in the table below: Mean Median Range Boys 27 seconds 26 seconds 25 seconds Girls 26.25 seconds 26.5 seconds 23 seconds The measures of center and spread for the boys and girls are similar in value. Two of the boys’ predictions are within 5 seconds of 30 seconds (26 and 35) and three of the girls predictions are within 5 seconds of 30 seconds (32, 33, and 34). (d) The box plots are shown below:
Jamie 19 F Leilani 20 F Reid 15 M Use the approaches below to determine how accurately the class predicted when 30 seconds has passed. (a) Find the mean, median and range for the predictions of when 30 seconds has passed for the class data. Describe how accurate the predictions were. How many of the predictions are within 5 seconds of 30 seconds? How many predictions are below 30 seconds? How many are above? (b) Produce a box plot of the prediction times. Describe the distribution of prediction times. (c) Find the mean, median and range for the predictions made by boys and for the predictions made by girls. Compare the accuracy of the predictions made by these two groups. (d) Produce separate box plots for the predictions made by the boys and girls. Compare the distributions. Answers: (a) The mean is 399/15 = 26.6 seconds. The ordered times are: 14 15 18 19 19 20 21 26 32 33 34 35 36 37 40 The median prediction is 26 seconds and the range is seconds. Eight students had a prediction that was less than 30 seconds and seven had a prediction that was more than 30 seconds. Five of the predictions are within 5 seconds of 30 seconds (26, 32, 33, 34 and 35). Interpretations: On average the predictions are about 3 or 4 seconds less than 30 seconds and the difference between the lowest and highest predictions is 26 seconds. (b) The box plot is shown below: The distribution is roughly symmetric. (c) The results are shown in the table below: Mean Median Range Boys 27 seconds 26 seconds 25 seconds Girls 26.25 seconds 26.5 seconds 23 seconds The measures of center and spread for the boys and girls are similar in value. Two of the boys’ predictions are within 5 seconds of 30 seconds (26 and 35) and three of the girls predictions are within 5 seconds of 30 seconds (32, 33, and 34). (d) The box plots are shown below:
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