Using a piece of graph paper, place values at equal distances along the x-axis, as shown in Figure 4.1. Now, identify the midpoint of each class interval, which is the middle point in the interval. It’s pretty easy to just eyeball, but you can also just add the top and bottom values of the class interval and divide by 2. For example, the midpoint of the class interval 0–4 is the average of 0 and 4, or 4/2 = 2. Draw a bar or column centered on each midpoint that represents the entire class interval to the height representing the frequency of that class interval. For example, in Figure 4.2, you
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