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### Measuring size range

Results
1) Use the class results [click here] to draw the following graphs:

• a frequency graph of height
• a frequency graph of head circumference
• a scatter graph of height against head circumference.
2 a) Calculate the average height for your class and mark that on your height graph.
b) Calculate the average head circumference for your class and mark that on your head circumference graph.
c) Use the graphs to calculate the range of height and of head circumference shown by your class.

3 Draw a line of best fit on your scatter graph.

Evaluation

4 a) Describe the shape of each of the two line graphs.
b) Do the results follow a normal distribution curve (like the one on page 39 of the Students’ Book)?
c i) If they do, what would have been the effect of taking fewer samples? (If you are using a spreadsheet program, you can test this by selecting small samples from your dataset and graphing them.)

ii) If they don’t, do you think you have enough data to answer research question A confidently?